Malicious PDF — malware analysis report

Static analysis result for SHA-256 36a1992b6171999e…

MALICIOUS

PDF

78.2 KB Created: 2021-07-30 03:07:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 88517bfebd8a8a7aeb06f0adf9632008 SHA-1: 606e3e76b401cd9a5e929ed2d8796366d565dcfa SHA-256: 36a1992b6171999eae7d134026c4efd4480ea59facccc5774d1ae950adfec5c8
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains a large number of embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to exploiting PDF vulnerabilities or delivering a secondary payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9987

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://comlark.ru/userfiles/files/xasepepamukudizejurigum.pdf
    • https://k9-warrior.com/wp-content/plugins/super-forms/uploads/php/files/n7om6utp0245i51b59tl1i86k5/gamasevaziwisi.pdf
    • http://mesahighclassof63.com/clients/79820/File/21904047604.pdf
    • https://www.sadcmedia.com/wp-content/plugins/super-forms/uploads/php/files/3c8kitq8kvhs3ut0qa2vng7rob/domudegamimuleba.pdf
    • https://hrmconsulting.biz/upload/files/69674117425.pdf
    • https://dezsredstvompx.ru/wp-content/plugins/super-forms/uploads/php/files/5671d239295ddec6e2d7c6ef3994a194/rirevemegegoturazabige.pdf
    • https://sonntag-immobilien.lu/userfiles/files/21555978870.pdf
    • https://amenagementsoleil.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a40d2d59d59---23776622838.pdf
    • http://bora.su/ckfinder/userfiles/files/ketibubupojo.pdf
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/l9bsnrk92uf5ita2vohk9ev4o4/98357624345.pdf
    • http://viettranslators.com/webroot/img/files/3730640236.pdf
    • http://okuninka-biale.pl/userfiles/file/kojewufutosemij.pdf
    • https://burragebrothers.com/demo/jolie/beta/userfiles/files/tidapip.pdf
    • http://sharon-barron.com/userfiles/files/zalikonidulavixameva.pdf
    • http://71mhsreunion.com/clients/f/fd/fd19d29f3ef40f7e1d0269d1df38e7d4/File/vatebesap.pdf
    • https://netlandschool.cl/files/gepivoxutejoxuxug.pdf
    • http://www.linkkorea.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/160a17745cf8c2---70568701402.pdf
    • http://akicgiyim.com/userfiles/file/dovititivariwewazoluteb.pdf
    • http://hydrem.ru/images/file/77339378872.pdf
    • http://wernitznigg.at/files/16762167770.pdf
    • http://bazab.ru/ckfinder/userfiles/files/13252296848.pdf
    • http://festivaldeliteraturadepereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a633efa75b8---lajoregegoz.pdf
    • https://mattweidnerlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/160845f3028e6f---rarerumajebojakokaju.pdf
    • http://malifer.hu/upload/file/36242112453.pdf
    • https://oddluzanie.net/userfiles/file/98269628230.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=properties+of+special+quadrilaterals+worksheet+pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_005_off0000ca7e.bin
99d80c83d0ec06c2b3284bfb4e506265c15c2b5dcabf5378b6b705919b3befc5
decompressed-pdf-stream PDF FlateDecoded stream at offset 0xCA7E 17468 bytes
font_01_sfnt_off0000f7ee.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF7EE 16792 bytes
font_02_sfnt_off00011005.bin
1f20dc4c8c011c9308cd441e371c2823c06d013782e7b2fec7bcc321e00a9cf6
pdf-font-stream PDF embedded font (sfnt) at offset 0x11005 11040 bytes