Malicious PDF — malware analysis report

Static analysis result for SHA-256 a59c90c81a8d3953…

MALICIOUS

PDF

77.5 KB Created: 2020-11-20 22:41:47 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: b6f72c55ae14c76d818c8363c851610b SHA-1: 1f7abae8abfac102e0a483b29770a5a8fc910b51 SHA-256: a59c90c81a8d39530f2118dcc1d3b42d13887f9704bca4c5ee1c71364eb70480
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains a critical heuristic firing for a malicious redirector link pointing to 'https://gettraff.ru/123?utm_term=and+then+there+were+none+1945'. This, combined with ML and ClamAV detections, strongly indicates malicious intent. The document body, though heavily obfuscated, contains metadata suggesting it was generated by wkhtmltopdf, a tool sometimes used to create malicious PDFs. No scripts were extracted, but the presence of a malicious URL is sufficient to classify this as a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 4

  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 https://gettraff.ru/123?utm_term=and+then+there+were+none+1945
    • https://cdn-cms.f-static.net/uploads/4366350/normal_5f8720a285e4d.pdf
    • https://cdn-cms.f-static.net/uploads/4369503/normal_5f8b240a3e0e4.pdf
    • https://cdn-cms.f-static.net/uploads/4375350/normal_5f92724c78f9b.pdf
    • https://cdn-cms.f-static.net/uploads/4494893/normal_5fabf7b61f8fd.pdf
    • https://cdn-cms.f-static.net/uploads/4368762/normal_5f8cc5e105017.pdf
    • https://cdn-cms.f-static.net/uploads/4379612/normal_5f96796c4a552.pdf
    • https://cdn-cms.f-static.net/uploads/4422627/normal_5fa4e76d935b0.pdf
    • https://cdn-cms.f-static.net/uploads/4426267/normal_5fa6ad3634d49.pdf
    • https://cdn-cms.f-static.net/uploads/4374177/normal_5f9389b18cff4.pdf
    • https://cdn-cms.f-static.net/uploads/4375209/normal_5f89dedb74799.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/lomiwexuva/21676070382.pdf
    • https://s3.amazonaws.com/zesotat/downtown_mafia_mob_hack.pdf
    • https://uploads.strikinglycdn.com/files/ec9a2395-291c-444b-b209-038f03d3703c/kivitodagef.pdf
    • https://uploads.strikinglycdn.com/files/21fcdbe7-7d00-4e96-ba90-502dc56a7384/verenezajilimomos.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://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f378.bin
f45d62b1ad98d0ac646f70e2ee795534c8c8553a95e3db9df214f7789c1ed847
pdf-font-stream PDF embedded font (sfnt) at offset 0xF378 4996 bytes
font_01_sfnt_off00010497.bin
ec5063e9d7bbd4857ac042da3cb236ba45d1e3f1dcc58ae6115e79a9671a067e
pdf-font-stream PDF embedded font (sfnt) at offset 0x10497 10700 bytes