Malicious PDF — malware analysis report

Static analysis result for SHA-256 8c7d6b8357bda5ea…

MALICIOUS

PDF

74.1 KB Created: 2021-06-01 05:28:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: e702ee6f66fb004d21d005320ed5866e SHA-1: bfaa22d0c6915d6f12a536c8505ed59ba14239fc SHA-256: 8c7d6b8357bda5eae6e0a2554fb88f711dae84dd787ee373d38b9aafcec64fc9
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many of which point to PDF files with generic names, suggesting a link farm or SEO poisoning tactic. The primary URL, 'https://ketchas.ru/pbw?utm_term=what+temperature+do+you+put+a+ham+in+the+oven', appears to be a lure to a phishing or malware distribution site. ClamAV and ML classifiers also flagged this PDF as malicious, specifically as a phishing trojan.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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://ketchas.ru/pbw?utm_term=what+temperature+do+you+put+a+ham+in+the+oven
    • https://luzusuzure.weebly.com/uploads/1/3/0/7/130775685/nejanodu-fimodiva-tepibal.pdf
    • https://gozajajemitala.weebly.com/uploads/1/3/4/3/134325553/sugig.pdf
    • https://cdn-cms.f-static.net/uploads/4403533/normal_602ac29c47f61.pdf
    • https://cdn-cms.f-static.net/uploads/4416513/normal_602d7b989839e.pdf
    • https://cdn-cms.f-static.net/uploads/4378618/normal_603388f6e8b8d.pdf
    • https://static.s123-cdn-static.com/uploads/4458144/normal_5fee958ecb734.pdf
    • https://cdn-cms.f-static.net/uploads/4416302/normal_603d0f481ac6b.pdf
    • https://cdn-cms.f-static.net/uploads/4464082/normal_606a8f42b3a25.pdf
    • https://static.s123-cdn-static.com/uploads/4389108/normal_5fc6d658b5cb4.pdf
    • https://static.s123-cdn-static.com/uploads/4455681/normal_5fed63faf226a.pdf
    • https://parimuxuroz.weebly.com/uploads/1/3/2/6/132682994/binazu.pdf
    • https://tenanetudoji.weebly.com/uploads/1/3/4/2/134266315/jelur.pdf
    • https://wejatinolu.weebly.com/uploads/1/3/1/4/131438249/walira_xawekozin.pdf
    • https://cdn-cms.f-static.net/uploads/4415768/normal_601608b752376.pdf
    • https://static.s123-cdn-static.com/uploads/4420775/normal_5fe20a8fc9f58.pdf
    • https://degufulu.weebly.com/uploads/1/3/1/3/131379990/2829525.pdf
    • https://cdn-cms.f-static.net/uploads/4446165/normal_603830c0c9d8b.pdf
    • https://welirupew.weebly.com/uploads/1/3/4/6/134662060/657ad.pdf
    • https://cdn-cms.f-static.net/uploads/4490930/normal_6029c5e537fbf.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/c613302a-e19b-4aa7-a412-3cdeeba09121/what_are_the_features_of_unix_operating_system.pdf
    • https://uploads.strikinglycdn.com/files/3b5e73fb-ec31-4041-a2de-e44504f81294/naglieri_scores_range.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_off0000e4fa.bin
7fe51f95c29bdc9c4a350fc8d080ed78a9bc7a333c7b795949dacfee5b1a16a2
pdf-font-stream PDF embedded font (sfnt) at offset 0xE4FA 5164 bytes
font_01_sfnt_off0000f672.bin
17df7e5abc2bd2fae2f73bbedda424c435eca25c98f80a1088c55e878b05638c
pdf-font-stream PDF embedded font (sfnt) at offset 0xF672 10516 bytes