Malicious PDF — malware analysis report

Static analysis result for SHA-256 83ce8f9c66fbc7c0…

MALICIOUS

PDF

73.3 KB Created: 2021-06-01 16:03:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 78da3b55aca7dbb820088f2a6adf24e5 SHA-1: f36a752e303f53418ad2dc0424722e5703520239 SHA-256: 83ce8f9c66fbc7c068e8be55d19c5dd16cf02d79afeb6cf60d857ce2a89199b2
164 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains a large number of external links, suggesting it's part of a link farm designed to direct users to potentially malicious websites. One of the embedded URLs, 'https://dafemum.ru/wb?keyword=how%20to%20change%20time%20on%20casio%20a178w%20watch', appears to be a lure, possibly for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 6

  • 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-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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://dafemum.ru/wb?keyword=how%20to%20change%20time%20on%20casio%20a178w%20watch
    • https://static.s123-cdn-static.com/uploads/4425784/normal_5fcb978c73cb0.pdf
    • https://cdn-cms.f-static.net/uploads/4469103/normal_6056b3bcaf576.pdf
    • https://static.s123-cdn-static.com/uploads/4414689/normal_5feb5faf9db87.pdf
    • https://cdn-cms.f-static.net/uploads/4413455/normal_60436cc052cfa.pdf
    • https://cdn-cms.f-static.net/uploads/4422914/normal_605d209fcdb4e.pdf
    • https://zefuriduzowav.weebly.com/uploads/1/3/0/7/130740504/xaditasazil.pdf
    • https://cdn-cms.f-static.net/uploads/4473640/normal_6051e3d925ef2.pdf
    • https://static.s123-cdn-static.com/uploads/4427091/normal_5fec6087a2635.pdf
    • https://cdn-cms.f-static.net/uploads/4366623/normal_6017dcef9c559.pdf
    • https://cdn-cms.f-static.net/uploads/4454168/normal_604f612c3d050.pdf
    • https://cdn-cms.f-static.net/uploads/4379489/normal_6069d0134019f.pdf
    • https://cdn-cms.f-static.net/uploads/4454422/normal_601689b62be62.pdf
    • https://pezilesuwubev.weebly.com/uploads/1/3/4/6/134639222/1600727.pdf
    • https://cdn-cms.f-static.net/uploads/4415740/normal_6039d24321f55.pdf
    • https://cdn-cms.f-static.net/uploads/4482189/normal_603a1f0dd58f2.pdf
    • https://dununatanag.weebly.com/uploads/1/3/0/7/130775655/5156559.pdf
    • https://static.s123-cdn-static.com/uploads/4368477/normal_5ff165a1e73c5.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/a804a0f4-4816-457b-9f82-43e10692fb00/52491778383.pdf
    • https://uploads.strikinglycdn.com/files/68cb29bf-a18e-4e10-aa89-6d50fb08ef0f/52079463247.pdf
    • https://uploads.strikinglycdn.com/files/e6916f54-e5fb-48c5-a5e1-395be9558066/98688167172.pdf
    • https://uploads.strikinglycdn.com/files/1ea9e532-97bc-4ed8-b03f-4dca6b152d02/tuzalusavusimof.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_off0000def2.bin
1222b3519819f35ab5e4bf4120e2bf1c5ffd8bc85695d2bb79161c28c4634d77
pdf-font-stream PDF embedded font (sfnt) at offset 0xDEF2 5464 bytes
font_01_sfnt_off0000f185.bin
c53714047346b541561aa98d36f11c278a5c19f3378c4283dc94b88c40e2fdbc
pdf-font-stream PDF embedded font (sfnt) at offset 0xF185 11160 bytes