{"id":5508,"date":"2025-06-30T10:22:00","date_gmt":"2025-06-30T08:22:00","guid":{"rendered":"https:\/\/www.websupport.cz\/blog\/?p=5508"},"modified":"2025-06-11T10:56:16","modified_gmt":"2025-06-11T08:56:16","slug":"co-je-to-spoofing-a-jak-se-branit","status":"publish","type":"post","link":"https:\/\/www.websupport.cz\/blog\/2025\/06\/co-je-to-spoofing-a-jak-se-branit\/","title":{"rendered":"Co je to spoofing a jak se br\u00e1nit?"},"content":{"rendered":"\n

Mo\u017en\u00e1 jste ji\u017e obdr\u017eeli e-mail ze zn\u00e1m\u00e9 e-mailov\u00e9 adresy, na kter\u00e9m bylo n\u011bco podivn\u00e9ho. Mo\u017en\u00e1 text zn\u011bl um\u011ble, mo\u017en\u00e1 tam byl odkaz, kter\u00fd vedl na nezn\u00e1mou adresu a \u017e\u00e1dal od v\u00e1s \u00fadaje. V\u011b\u0159\u00edme, \u017ee jste (i d\u00edky na\u0161im \u010dl\u00e1nk\u016fm o phishingu<\/a>) na tento odkaz neklikli a ochr\u00e1nili tak sv\u00e9 pen\u00edze i soukrom\u00ed.<\/p>\n\n\n\n

Probl\u00e9m nastane, pokud n\u011bkdo zneu\u017eije va\u0161i dom\u00e9nu k rozes\u00edl\u00e1n\u00ed phishingu nebo spoofingu. Za ur\u010dit\u00fdch okolnost\u00ed to nen\u00ed tak t\u011b\u017ek\u00e9 a d\u016fsledky pro v\u00e1s mohou b\u00fdt nep\u0159\u00edjemn\u00e9. Proto je t\u0159eba v\u011bd\u011bt, o co jde a jak se takov\u00e9mu riziku vyhnout.<\/p>\n\n\n\n

Co je spoofing?<\/h2>\n\n\n\n

Spoofing je zp\u016fsob kybernetick\u00e9ho \u00fatoku, kter\u00fd spo\u010d\u00edv\u00e1 v zakryt\u00ed skute\u010dn\u00e9 identity \u00fato\u010dn\u00edka d\u016fv\u011bryhodnou nebo zn\u00e1mou identitou<\/strong>. C\u00edlem je vyu\u017e\u00edt d\u016fv\u011bru a zm\u00e1st vybranou ob\u011b\u0165 \u00fatoku. Zjednodu\u0161en\u011b \u0159e\u010deno \u2013 podvodn\u00edk chce rozeslat virus nebo odkaz na fale\u0161n\u00fd web a na n\u011bm okr\u00e1dat lidi o pen\u00edze nebo \u00fadaje. Proto si najde d\u016fv\u011bryhodnou dom\u00e9nu, ze kter\u00e9 e-maily rozes\u00edl\u00e1. Takovou dom\u00e9nou m\u016f\u017ee b\u00fdt i ta va\u0161e, pokud m\u00e1 nap\u0159\u00edklad v \u00famyslu po\u0161kodit reputaci va\u0161\u00ed firmy ve prosp\u011bch konkurence.<\/p>\n\n\n\n

Takto m\u016f\u017ee nap\u0159\u00edklad \u00fa\u010detn\u00ed dostat do schr\u00e1nky e-mail od \u0161\u00e9fa, \u017ee je t\u0159eba zaplatit fakturu. Pracovn\u00ed e-mailov\u00e1 adresa \u0161\u00e9fa sed\u00ed a \u00fa\u010detn\u00ed platbu provede. Jen\u017ee \u0161\u00e9f o ni\u010dem nev\u00ed. P\u0159esn\u011b tak se to stalo p\u0159ed n\u011bkolika lety v\u00fdrobci panenek Barbie, spole\u010dnosti Mattel, kter\u00e1 \u201ed\u00edky\u201c spoofingu p\u0159i\u0161la o 3 miliony dolar\u016f, kter\u00e9 skon\u010dily n\u011bkde v \u010c\u00edn\u011b.<\/p>\n\n\n\n

Spoofing se krom\u011b e-mailov\u00e9 adresy m\u016f\u017ee t\u00fdkat i zneu\u017eit\u00ed telefonn\u00edho \u010d\u00edsla k zas\u00edl\u00e1n\u00ed podvodn\u00fdch SMS<\/strong> nebo phishingov\u00fdch hovor\u016f ze zn\u00e1m\u00fdch \u010d\u00edsel<\/strong>, kdy \u00fato\u010dn\u00edci zm\u011bn\u00ed zobrazen\u00e9 \u010d\u00edslo volaj\u00edc\u00edho, aby adres\u00e1t p\u0159ijal hovor v domn\u011bn\u00ed, \u017ee volaj\u00edc\u00edho zn\u00e1.<\/p>\n\n\n\n

Jak k podvodu doch\u00e1z\u00ed? P\u0159\u00ed\u010din m\u016f\u017ee b\u00fdt n\u011bkolik.<\/p>\n\n\n\n

Jak funguje spoofing?<\/h2>\n\n\n\n

Nezabezpe\u010den\u00e9 SMTP a SMPT relay servery<\/h3>\n\n\n\n

Pokud n\u011bkdo zneu\u017eije dom\u00e9nu k rozes\u00edl\u00e1n\u00ed fale\u0161n\u00fdch e-mail\u016f, z\u00e1kladn\u00edm probl\u00e9mem m\u016f\u017ee b\u00fdt nezabezpe\u010den\u00fd SMTP port<\/strong>. O co jde? Server, kter\u00fd odes\u00edl\u00e1 e-maily z va\u0161\u00ed dom\u00e9ny, p\u0159ij\u00edm\u00e1 p\u0159es SMTP port po\u017eadavky na odes\u00edl\u00e1n\u00ed e-mail\u016f nejen ze stejn\u00e9 dom\u00e9ny, ale i od t\u0159et\u00edch stran. Nap\u0159\u00edklad pokud pov\u011b\u0159\u00edte rozes\u00edl\u00e1n\u00edm newsletteru marketingovou agenturu.<\/p>\n\n\n\n

Pokud je SMPT port otev\u0159en\u00fd (tj. nezabezpe\u010den\u00fd, nechr\u00e1n\u011bn\u00fd), nen\u00ed v\u016fbec t\u011b\u017ek\u00e9 takov\u00fd port naj\u00edt. Existuj\u00ed slu\u017eby, kter\u00e9 prohled\u00e1vaj\u00ed cel\u00fd internet a poskytuj\u00ed tuto informaci komukoli. \u010casto zcela zdarma.<\/p>\n\n\n\n

Pot\u00e9 sta\u010d\u00ed \u00fato\u010dn\u00edkovi zadat p\u0159\u00edslu\u0161n\u00e9 sou\u0159adnice na nechr\u00e1n\u011bn\u00fd SMTP port a m\u016f\u017ee z dan\u00e9 adresy vesele rozes\u00edlat e-maily. Majitel e-mailov\u00e9 adresy o tom \u010dasto ani nebude v\u011bd\u011bt. Odeslan\u00e9 e-maily se toti\u017e neukl\u00e1daj\u00ed v jeho e-mailov\u00e9 schr\u00e1nce.<\/strong><\/p>\n\n\n\n

Chyb\u011bj\u00edc\u00ed nebo nespr\u00e1vn\u00fd z\u00e1znam SPF<\/h3>\n\n\n\n

SPF z\u00e1znam je textov\u00fd seznam (whitelist) p\u0159edem ur\u010den\u00fdch IP adres (SMTP server\u016f), kter\u00e9 jako jedin\u00e9 jsou opr\u00e1vn\u011bny odes\u00edlat e-maily z va\u0161\u00ed dom\u00e9ny. \u00dato\u010dn\u00edk, kter\u00fd zad\u00e1 po\u017eadavek na v\u00e1\u0161 server k odesl\u00e1n\u00ed podvodn\u00e9ho e-mailu, bude tedy jednodu\u0161e zablokov\u00e1n, proto\u017ee jeho IP adresa se v dan\u00e9m seznamu nenach\u00e1z\u00ed.<\/p>\n\n\n\n

C\u00edlem spr\u00e1vn\u00e9ho nastaven\u00ed z\u00e1znamu SPF je omezit mo\u017enost zfal\u0161ov\u00e1n\u00ed odes\u00edlatele (spoofing) a zabr\u00e1nit tak spamu i phishingu.<\/strong><\/p>\n\n\n\n

Hacknut\u00e9 e-mailov\u00e9 schr\u00e1nky<\/h3>\n\n\n\n

Pokud nezabezpe\u010d\u00edte svou e-mailovou schr\u00e1nku dostate\u010dn\u011b siln\u00fdm heslem nebo t\u00edmto heslem nechr\u00e1n\u00edte za\u0159\u00edzen\u00ed (nej\u010dast\u011bji mobiln\u00ed telefon), na kter\u00e9m m\u00e1te otev\u0159en\u00fd sv\u016fj e-mail, m\u016f\u017ee doj\u00edt k z\u00edsk\u00e1n\u00ed p\u0159\u00edstupu k cel\u00e9mu obsahu va\u0161eho za\u0159\u00edzen\u00ed, v\u010detn\u011b e-mailov\u00e9 schr\u00e1nky.<\/strong><\/p>\n\n\n\n

Podvodn\u00edk m\u016f\u017ee v takov\u00e9m p\u0159\u00edpad\u011b tento p\u0159\u00edstup zneu\u017e\u00edt k rozes\u00edl\u00e1n\u00ed obsahu podle libosti.<\/p>\n\n\n\n

Nezabezpe\u010den\u00e9 kontaktn\u00ed formul\u00e1\u0159e<\/h3>\n\n\n\n

Kontaktn\u00ed formul\u00e1\u0159 je obl\u00edben\u00fd a \u010dast\u00fd zp\u016fsob, jak n\u00e1v\u0161t\u011bvn\u00edk\u016fm webu umo\u017enit kontaktovat majitele webu. N\u00e1v\u0161t\u011bvn\u00edk nap\u00ed\u0161e zpr\u00e1vu, zanech\u00e1 na sob\u011b e-mail a zpr\u00e1vu ode\u0161le okam\u017eit\u011b. Majiteli webu tato zpr\u00e1va p\u0159ijde do jeho e-mailu a jako odes\u00edlatel je uveden jeho vlastn\u00ed web.<\/p>\n\n\n\n

Pokud kontaktn\u00ed formul\u00e1\u0159 nen\u00ed \u0159\u00e1dn\u011b zabezpe\u010den, \u00fato\u010dn\u00edk m\u016f\u017ee zm\u011bnit adres\u00e1ta z majitele webu na kohokoli jin\u00e9ho.<\/strong> Tak m\u016f\u017ee zpr\u00e1vu z d\u016fv\u011bryhodn\u00e9ho webu rozeslat i tis\u00edc\u016fm adres\u00e1t\u016f. E-mail m\u016f\u017ee vypadat jako zpr\u00e1va z va\u0161eho obl\u00edben\u00e9ho e-shopu nebo banky, odes\u00edlatel bude stejn\u00fd jako v\u017edy, ale obsah m\u016f\u017ee b\u00fdt fale\u0161n\u00fd.<\/p>\n\n\n\n

M\u016f\u017eete tak kliknout na virus nebo zadat platebn\u00ed \u00fadaje v domn\u011bn\u00ed, \u017ee je v\u00e1\u0161 e-shop pot\u0159ebuje nap\u0159\u00edklad k vr\u00e1cen\u00ed pen\u011bz. Ve skute\u010dnosti o n\u011b m\u016f\u017eete v dobr\u00e9 v\u00ed\u0159e p\u0159ij\u00edt.<\/p>\n\n\n\n

N\u011bkdy k takov\u00e9mu \u00fatoku sta\u010d\u00ed jen m\u00edrn\u011b pokro\u010dil\u00e1 znalost jazyka HTML. \u00dato\u010dn\u00edk m\u016f\u017ee nap\u0159\u00edklad do textov\u00e9ho pole kontaktn\u00edho formul\u00e1\u0159e (tj. \u010d\u00e1sti formul\u00e1\u0159e, kde p\u00ed\u0161ete svou zpr\u00e1vu nebo vypl\u0148ujete sv\u00e9 \u00fadaje) napsat k\u00f3d, kter\u00fd se naz\u00fdv\u00e1 \u201einjekce\u201c (injection). Takto vlo\u017een\u00fd k\u00f3d v podstat\u011b p\u0159ep\u00ed\u0161e p\u016fvodn\u00ed k\u00f3d <\/strong>(p\u0159edk\u00f3dovan\u00e9 \u00fadaje) kontaktn\u00edho formul\u00e1\u0159e. A e-maily se mohou bez probl\u00e9m\u016f rozes\u00edlat. A to bez v\u011bdom\u00ed majitele webu.<\/p>\n\n\n\n

Zavirovan\u00fd mobiln\u00ed telefon nebo po\u010d\u00edta\u010d<\/h3>\n\n\n\n

Pokud nen\u00ed antivirov\u00fd program pravideln\u011b aktualizov\u00e1n nebo spu\u0161t\u011bn, m\u016f\u017eete si zavirovat vlastn\u00ed za\u0159\u00edzen\u00ed. Nej\u010dast\u011bji se virus m\u016f\u017ee dostat do va\u0161eho mobiln\u00edho telefonu nebo po\u010d\u00edta\u010de p\u0159i n\u00e1v\u0161t\u011bv\u011b r\u016fzn\u00fdch pochybn\u00fdch str\u00e1nek, kliknut\u00edm na nezn\u00e1m\u00e9 odkazy nebo otev\u0159en\u00edm p\u0159\u00edloh v e-mailech.<\/strong><\/p>\n\n\n\n

V takov\u00e9m p\u0159\u00edpad\u011b m\u016f\u017ee \u00fato\u010dn\u00edk sledovat ve\u0161kerou va\u0161i komunikaci, ovl\u00e1dnout cel\u00e9 va\u0161e za\u0159\u00edzen\u00ed a tak\u00e9 z n\u011bj rozes\u00edlat pod va\u0161\u00edm jm\u00e9nem podvodn\u00e9 e-maily.<\/p>\n\n\n\n

Jak se vyhnout spoofingu?<\/h2>\n\n\n\n

Siln\u00e9 heslo a opatrn\u00fd p\u0159\u00edstup<\/h3>\n\n\n\n

Siln\u00e9 heslo je z\u00e1kladn\u00edm opat\u0159en\u00edm v digit\u00e1ln\u00edm sv\u011bt\u011b, ide\u00e1ln\u011b pro v\u0161echny slu\u017eby. A dvoufaktorov\u00e1 autentizace<\/strong> v\u0161ude, kde je to mo\u017en\u00e9. Pouh\u00fdm dodr\u017eov\u00e1n\u00edm tohoto zlat\u00e9ho pravidla bezpe\u010dnosti na internetu m\u016f\u017eete v\u00fdrazn\u011b sn\u00ed\u017eit riziko. A nic to nestoj\u00ed.<\/p>\n\n\n\n

Tak\u00e9 se sna\u017ete v\u017edy pou\u017e\u00edvat zabezpe\u010den\u00e9 protokoly (HTTPS)<\/strong> pro webov\u00e9 str\u00e1nky a vyh\u00fdbejte se p\u0159\u00edstupu na internet p\u0159es nezabezpe\u010den\u00e9 ve\u0159ejn\u00e9 wifi. Pokud mus\u00edte, p\u0159ipojujte se rad\u011bji p\u0159es VPN slu\u017ebu.<\/strong><\/p>\n\n\n\n

Spr\u00e1vn\u00e9 nastaven\u00ed SPF, DKIM a DMARC z\u00e1znamu<\/h3>\n\n\n\n

Pokud odes\u00edl\u00e1te e-maily od n\u00e1s z Websupportu, m\u016f\u017eete si SPF z\u00e1znam nastavit rychle a snadno<\/a>. Nejen\u017ee zabr\u00e1n\u00edte zneu\u017eit\u00ed, ale tak\u00e9 zlep\u0161\u00edte doru\u010ditelnost sv\u00fdch e-mail\u016f.<\/strong><\/p>\n\n\n\n

Stejn\u011b tak je u\u017eite\u010dn\u00e9 m\u00edt zapnutou technologii DKIM. To znamen\u00e1, \u017ee ka\u017ed\u00fd e-mail odeslan\u00fd z va\u0161eho serveru bude p\u0159edem ov\u011b\u0159en a autorizov\u00e1n p\u0159edem nastaven\u00fdm zp\u016fsobem<\/strong>. \u017d\u00e1dn\u00fd \u00fato\u010dn\u00edk zven\u010d\u00ed pak nebude schopen (nebo jen velmi obt\u00ed\u017en\u011b) odes\u00edlat podvodn\u00e9 e-maily z va\u0161eho \u00fa\u010dtu. U n\u00e1s je v r\u00e1mci hostingu automaticky zapnut\u00e1. M\u016f\u017eete si to snadno zkontrolovat<\/a>.<\/p>\n\n\n\n

Vypnut\u00e1 technologie DMARC zase znamen\u00e1, \u017ee SPF a DKIM nejsou pln\u011b vyu\u017eity.<\/p>\n\n\n\n

DMARC je ur\u010ditou nadstavbou pro SPF a DKIM, kter\u00e1 tyto dv\u011b opat\u0159en\u00ed kombinuje. Specifikace DMARC se pou\u017e\u00edv\u00e1 k informov\u00e1n\u00ed serveru p\u0159ij\u00edmaj\u00edc\u00edho e-maily o tom, jak se m\u00e1 chovat p\u0159i doru\u010dov\u00e1n\u00ed zpr\u00e1v z ur\u010dit\u00e9 dom\u00e9ny. Zjednodu\u0161en\u011b \u0159e\u010deno, technologie DMARC m\u00e1 za \u00fakol pomoc\u00ed SPF a DKIM ov\u011b\u0159it, zda p\u0159\u00edchoz\u00ed e-mail byl skute\u010dn\u011b odesl\u00e1n z dom\u00e9ny uveden\u00e9 v hlavi\u010dce odes\u00edlatele.<\/strong><\/p>\n\n\n\n

DMARC tak\u00e9 um\u00ed nastavit pravidla, jak zach\u00e1zet s neov\u011b\u0159en\u00fdmi e-maily, a pr\u016fb\u011b\u017en\u011b informovat v\u00e1s jako spr\u00e1vce dom\u00e9ny odes\u00edlatele o v\u00fdsledc\u00edch.<\/p>\n\n\n\n

Zaj\u00edmavost\u00ed je, \u017ee od \u00fanora 2024 se od poskytovatel\u016f e-mailov\u00fdch slu\u017eeb, jako jsou Gmail a Yahoo, vy\u017eaduje, aby odes\u00edlatel\u00e9, kte\u0159\u00ed odes\u00edlaj\u00ed hromadn\u00e9 e-maily (v\u00edce ne\u017e 5000 denn\u011b), m\u011bli povinn\u011b nastaven\u00fd z\u00e1znam DMARC.<\/em><\/p>\n\n\n\n

Aktualizace a antivirov\u00e9 skenov\u00e1n\u00ed<\/h3>\n\n\n\n

N\u011bkdy jsme tak zanepr\u00e1zdn\u011bni, \u017ee ignorujeme hl\u00e1\u0161ky o nutnosti aktualizace (update) antivirov\u00fdch klient\u016f, prohl\u00ed\u017ee\u010d\u016f, opera\u010dn\u00edch syst\u00e9m\u016f, aplikac\u00ed a kdo v\u00ed \u010deho je\u0161t\u011b. Klikneme na Pozd\u011bji a pokra\u010dujeme v pr\u00e1ci. To je p\u0159esn\u011b ten moment, kdy m\u016f\u017ee b\u00fdt n\u00e1\u0161 syst\u00e9m zraniteln\u00fd.<\/p>\n\n\n\n

    \n
  1. <\/li>\n<\/ol>\n\n\n\n

    Pokud se pravideln\u011b star\u00e1me o \u010distotu na\u0161eho auta nebo domu, nezapom\u00ednejme ani na \u201e\u010distotu\u201c na\u0161ich za\u0159\u00edzen\u00ed a syst\u00e9m\u016f. Pr\u00e1v\u011b pravideln\u00fdmi aktualizacemi<\/strong> zaji\u0161\u0165ujeme jejich ochranu p\u0159ed nejnov\u011bj\u0161\u00edmi hrozbami.<\/p>\n\n\n\n

    Toto z\u00e1kladn\u00ed pravidlo plat\u00ed o to v\u00edce pro antivirov\u00fd program. Konkr\u00e9tn\u011b pro jeho aktualizaci a pravideln\u00e9 spou\u0161t\u011bn\u00ed skenov\u00e1n\u00ed va\u0161eho za\u0159\u00edzen\u00ed. Pokud to v\u00e1\u0161 antivirov\u00fd program ned\u011bl\u00e1 automaticky, zapn\u011bte tuto funkci ru\u010dn\u011b. Nebo ho vym\u011b\u0148te za lep\u0161\u00ed.<\/p>\n\n\n\n

    V\u011bt\u0161ina antivirov\u00fdch program\u016f obsahuje tak\u00e9 br\u00e1nu firewall<\/strong>, kter\u00e1 (pokud je spr\u00e1vn\u011b nakonfigurov\u00e1na) chr\u00e1n\u00ed va\u0161e za\u0159\u00edzen\u00ed p\u0159ed \u00fatoky zven\u010d\u00ed t\u00edm, \u017ee filtruje p\u0159\u00edstupy k jednotliv\u00fdm port\u016fm nebo pou\u017e\u00edvan\u00fdm program\u016fm, stejn\u011b jako p\u0159ed \u00fanikem dat z va\u0161eho za\u0159\u00edzen\u00ed sm\u011brem ven.<\/p>\n\n\n\n

    Jak postupovat, kdy\u017e dojde ke spoofingu?<\/h2>\n\n\n\n

    Pokud si z\u00e1kazn\u00edk va\u0161eho webu nebo e-shopu st\u011b\u017euje, \u017ee mu z va\u0161eho e-mailu p\u0159i\u0161ly n\u011bjak\u00e9 podez\u0159el\u00e9 zpr\u00e1vy (gratulujeme v\u00e1m k uv\u011bdom\u011bl\u00fdm z\u00e1kazn\u00edk\u016fm), doporu\u010dujeme v\u00e1m nejprve zjistit, co se stalo. Konkr\u00e9tn\u011b, zda ke zneu\u017eit\u00ed dom\u00e9ny do\u0161lo v d\u016fsledku \u00faniku p\u0159ihla\u0161ovac\u00edch \u00fadaj\u016f jednoho nebo v\u00edce zam\u011bstnanc\u016f nebo neopr\u00e1vn\u011bn\u00e9ho p\u0159\u00edstupu k IT syst\u00e9m\u016fm z jin\u00e9ho d\u016fvodu.<\/p>\n\n\n\n

    Pokud se jedn\u00e1 o zneu\u017eit\u00ed zam\u011bstnaneck\u00e9ho \u00fa\u010dtu, m\u016f\u017eete p\u0159ej\u00edt ke kroku 2.<\/p>\n\n\n\n

    1) Kontrola a vy\u010di\u0161t\u011bn\u00ed za\u0159\u00edzen\u00ed <\/h3>\n\n\n\n

    Kontrola potenci\u00e1ln\u011b dot\u010den\u00fdch za\u0159\u00edzen\u00ed je prvn\u00edm kl\u00ed\u010dov\u00fdm krokem. Nejprve je nutn\u00e9 dot\u010den\u00e1 za\u0159\u00edzen\u00ed p\u0159ev\u00e9st do offline re\u017eimu a zkontrolovat, zda do\u0161lo k neopr\u00e1vn\u011bn\u00e9mu p\u0159\u00edstupu do syst\u00e9m\u016f nebo k infikov\u00e1n\u00ed virem (malwarem)<\/strong>. K tomu v\u00e1m pomohou r\u016fzn\u00e1 bezpe\u010dnostn\u00ed \u0159e\u0161en\u00ed (antivirov\u00e9 syst\u00e9my) a va\u0161e p\u0159\u00edstupov\u00e9 z\u00e1znamy (logs). Pokud si s t\u00edm nev\u00edte rady, obra\u0165te se na IT odborn\u00edka.<\/p>\n\n\n\n

    Okam\u017eit\u00e1 zm\u011bna hesel<\/h3>\n\n\n\n

    P\u0159ed op\u011btovn\u00fdm uveden\u00edm za\u0159\u00edzen\u00ed do provozu je nutn\u00e9 zm\u011bnit hesla k va\u0161\u00ed e-mailov\u00e9 schr\u00e1nce, administra\u010dn\u00edmu rozhran\u00ed va\u0161eho webu a zejm\u00e9na k samotn\u00fdm za\u0159\u00edzen\u00edm. <\/strong>Pokud m\u00e1te z\u0159\u00edzen\u00e9 tak\u00e9 p\u0159\u00edstupov\u00e9 \u00fa\u010dty va\u0161ich zam\u011bstnanc\u016f nebo jak\u00e9koli servisn\u00ed \u00fa\u010dty k server\u016fm, nechte resetovat v\u0161echny p\u0159\u00edstupy a hesla. A pou\u010dte zam\u011bstnance, aby si nastavili nov\u00e9 (nov\u00e9!) a siln\u00e9 heslo.<\/p>\n\n\n\n

    Oprava z\u00e1znam\u016f SPF\/DKIM\/DMARC<\/h3>\n\n\n\n

    Dal\u0161\u00edm krokem, kter\u00fd m\u016f\u017eete pom\u011brn\u011b rychle prov\u00e9st, je zkontrolovat spr\u00e1vnost nastaven\u00ed a zapnut\u00ed z\u00e1znam\u016f SPF, DKIM, DMARC. M\u016f\u017eete to ud\u011blat sami nebo n\u00e1s kontaktovat na na\u0161\u00ed z\u00e1kaznick\u00e9 podpo\u0159e, r\u00e1di v\u00e1m pom\u016f\u017eeme.<\/p>\n\n\n\n

      \n
    1. <\/li>\n<\/ol>\n\n\n\n

      Kter\u00e9 e-maily mohou b\u00fdt podvodn\u00e9?<\/h2>\n\n\n\n

      Fale\u0161n\u00e9 e-maily jsou d\u00edky technologi\u00edm s um\u011blou inteligenc\u00ed st\u00e1le t\u011b\u017e\u0161\u00ed rozpoznat na prvn\u00ed pohled. V\u0161\u00edmejte si zejm\u00e9na, zda:<\/p>\n\n\n\n

        \n
      • text p\u016fsob\u00ed jako strojov\u00fd p\u0159eklad z jin\u00e9ho jazyka, \u010dasto m\u00e1 nal\u00e9hav\u00fd t\u00f3n,<\/strong><\/li>\n\n\n\n
      • e-mail obsahuje \u010detn\u00e9 gramatick\u00e9 nebo pravopisn\u00e9 chyby,<\/li>\n\n\n\n
      • m\u00e1 banka\/\u0161kola\/e-shop v\u016fbec d\u016fvod pos\u00edlat e-mail s dan\u00fdm obsahem a p\u0159\u00edpadn\u011b si to p\u0159\u00edmo u nich ov\u011b\u0159te.<\/strong><\/li>\n<\/ul>\n\n\n\n

        <\/p>\n\n\n\n

        V\u017edy bu\u010fte opatrn\u00ed, d\u016fv\u011b\u0159ujte sv\u00fdm instinkt\u016fm a neklikejte na nic bez rozmyslu.<\/p>\n","protected":false},"excerpt":{"rendered":"

        Mo\u017en\u00e1 jste ji\u017e obdr\u017eeli e-mail ze zn\u00e1m\u00e9 e-mailov\u00e9 adresy, na kter\u00e9m bylo n\u011bco podivn\u00e9ho. Mo\u017en\u00e1 text zn\u011bl um\u011ble, mo\u017en\u00e1 tam byl odkaz, kter\u00fd vedl na nezn\u00e1mou adresu a \u017e\u00e1dal od v\u00e1s \u00fadaje. V\u011b\u0159\u00edme, \u017ee jste (i d\u00edky na\u0161im \u010dl\u00e1nk\u016fm o phishingu) na tento odkaz neklikli a ochr\u00e1nili tak sv\u00e9 pen\u00edze i soukrom\u00ed. Probl\u00e9m nastane, pokud […]<\/p>\n","protected":false},"author":48,"featured_media":5511,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[575],"tags":[20,578,19],"class_list":["post-5508","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-bezpecnost","tag-bezpecnost","tag-phishing","tag-websupport"],"yoast_head":"\nCo je to spoofing a jak se br\u00e1nit? - Websupport.cz Blog<\/title>\n<meta name=\"description\" content=\"Zjist\u011bte, co je spoofing, jak funguje a jak se p\u0159ed n\u00edm efektivn\u011b br\u00e1nit. 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