Malicious PDF — malware analysis report

Static analysis result for SHA-256 7b6f733d1e5f1170…

MALICIOUS

PDF

83.7 KB Created: 2021-07-03 19:11:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a52acf52a878334e46e689cbfdfefb62 SHA-1: 524268920e4be98a5cf728eeb43b20e728e59481 SHA-256: 7b6f733d1e5f1170bfafd08fd6041be85f508fbc94d871f7dfffb81a79f539b1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm pointing to compromised CMS uploads and disposable hosting, suggesting a phishing or malware distribution scheme. The document body was heavily obfuscated and unreadable, providing no direct content clues, but the overall structure and URL targets strongly suggest a malicious purpose.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9860

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://www.segurosfacility.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b3f072c6954---xixozodivo.pdf
    • https://bringem.de/wp-content/plugins/super-forms/uploads/php/files/7aec78bb11fcc6f84e61a9925244da26/73578481681.pdf
    • https://fortlauderdale-carservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a8fb556212d---91271325413.pdf
    • https://kfz-gutachter-oliver-schiller.de/wp-content/plugins/formcraft/file-upload/server/content/files/160d86c146958a---5426157361.pdf
    • http://www.chicagoalphas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a4a2b800da---95029466125.pdf
    • http://handbook.hu/upload/page/file/fifusabotuvigo.pdf
    • https://subarini.ro/mm/file/pezoxux.pdf
    • https://www.nestroots.com/wp-content/plugins/super-forms/uploads/php/files/p1e8eh4qrph5np0es7o5in9i02/5657627402.pdf
    • http://healthywithhart.com/res/file/3986627790.pdf
    • https://trichynext.com/wp-content/plugins/super-forms/uploads/php/files/c4f1e8773ac037d346cdf9124bab39ef/98501827750.pdf
    • http://www.guaitoli.eng.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607d5e7fb9282---sitan.pdf
    • https://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/u5op9258s3rfpuh911pgrlecd7/wokapuwepidasuz.pdf
    • https://malimbe.africa/wp-content/plugins/super-forms/uploads/php/files/2f72760755fd4ae8abe7c87a2b67f8b2/17158858017.pdf
    • http://www.tramag.pl/upload/file/31542524665.pdf
    • https://mebelihome.ru/upload_picture/77328817108.pdf
    • https://agrachoff.ru/wp-content/plugins/super-forms/uploads/php/files/1807ba5638782c23317de2dd0905ae90/51115424040.pdf
    • https://tocgia247.com/wp-content/plugins/super-forms/uploads/php/files/o0gvqgj8v9mqmd4ba1u117mj5b/506497061.pdf
    • https://macleanpinesdrivingschool.com.au/wp-content/plugins/super-forms/uploads/php/files/56d7a8df3a565043e73e60a5d859fbde/fijeveki.pdf
    • https://socialchangefactory.org/wp-content/plugins/super-forms/uploads/php/files/7e9c843fbfd5b551bddff44609872508/60776887530.pdf
    • http://beijingbeat.com/contents//files/nabavanuzufukadeza.pdf
    • https://hitourkorea.com/FileData/ckfinder/files/20210630_5201136A3AFBAEA4.pdf
    • http://www.auditsi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c67aee0dfb---43875611979.pdf
    • https://plentis.eu/ckfinder/userfiles/files/nudofuzovegefuraxosupepo.pdf
    • http://studiotecnicodavico.eu/userfiles/files/60956122892.pdf
    • https://abugfreemind.com/userfiles/file/17268934846.pdf
    • https://udachi.co.th/wp-content/plugins/super-forms/uploads/php/files/s2obf5r0bqctihpodtnrd41bbo/74255272490.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=a+link+remove+underline
    • 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
font_00_sfnt_off0000e2ec.bin
96f894b237c2ce96dd68208d54f6776863e6a272bed03940a5da31ae0742f3a0
pdf-font-stream PDF embedded font (sfnt) at offset 0xE2EC 10220 bytes
font_01_sfnt_off0000f9c4.bin
de3a4a04a8a6a0dcfd111b2bd0b2c9f12f20a921cdd145999456fcf87e2be304
pdf-font-stream PDF embedded font (sfnt) at offset 0xF9C4 18112 bytes
font_02_sfnt_off00012945.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12945 16792 bytes