Malicious PDF — malware analysis report

Static analysis result for SHA-256 2a25da76db0ae9c0…

MALICIOUS

PDF

71.2 KB Created: 2020-11-11 22:46:58 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: d0c89d2c9e735f640d38283e8ab40581 SHA-1: 2dc76eb8563f497df7a8228ba053578241e08a06 SHA-256: 2a25da76db0ae9c07d99d8374ab1f409eda62fd2b0205bf5d2a17eb50243aefd
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, with one heuristic specifically identifying it as a 'PDF_SEO_LINK_FARM'. The presence of a malicious ML classification and ClamAV detection further supports its malicious nature. The primary IOC is the link to 'traffine.ru', which is likely part of a phishing or content-luring scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 5

  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 https://traffine.ru/123?utm_term=when+dinosaurs+roamed+america+stegosaurus
    • https://cdn-cms.f-static.net/uploads/4366017/normal_5f87031ce7603.pdf
    • https://zajefepitav.weebly.com/uploads/1/3/4/2/134266194/jifojajibunujepepis.pdf
    • https://cdn-cms.f-static.net/uploads/4366035/normal_5f8bf2088da8d.pdf
    • https://cdn-cms.f-static.net/uploads/4368222/normal_5f94e18f7f0a2.pdf
    • https://cdn-cms.f-static.net/uploads/4412775/normal_5f95cc0e2e633.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/pafiganovavi/to_whom_it_may_concern_letter_examples.pdf
    • https://s3.amazonaws.com/wukevirenesu/28202977907.pdf
    • https://s3.amazonaws.com/nokiva/zilakomozapigu.pdf
    • https://s3.amazonaws.com/pazovugal/nate_mack_elementary_henderson.pdf
    • https://s3.amazonaws.com/fasanag/bugler_s_holiday_leroy_anderson.pdf
    • https://s3.amazonaws.com/purufiz/8073349396.pdf
    • https://s3.amazonaws.com/mijedusovineti/edward_snowden_book_free.pdf
    • https://uploads.strikinglycdn.com/files/1bfd289e-7b45-48d2-a468-e6dd15567b90/imanes_artificiales_como_se_obtienen.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_off0000d708.bin
6e5bac595218240362e3751dd6575151e1aca14e57433251a09089058944d769
pdf-font-stream PDF embedded font (sfnt) at offset 0xD708 5336 bytes
font_01_sfnt_off0000e910.bin
fdb94683dc36dd67926e9cc68b95dc165dece072fced0d6e691517d77fbc9c28
pdf-font-stream PDF embedded font (sfnt) at offset 0xE910 11692 bytes