Malicious PDF — malware analysis report

Static analysis result for SHA-256 50b85dd9614e17dc…

MALICIOUS

PDF

87.5 KB Created: 2021-03-29 12:01:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: e06e8d818fc11979dabe95167b65d357 SHA-1: d8543f47219ddcce77ea3a29863a4b420142b0ea SHA-256: 50b85dd9614e17dc336d9d08c584e79f6bb1e239573b5010a7e0be4233e73699
164 Risk Score

Malware Insights

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

The PDF contains a large number of embedded external links, a technique often used for SEO farms or to distribute malicious content, as indicated by the 'PDF_SEO_LINK_FARM' heuristic. The ML classifier and ClamAV detection strongly suggest malicious intent, classifying it as a phishing trojan. While no scripts were directly extracted, the presence of external links and the nature of the heuristics point towards a phishing or content distribution attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://vilenefex.ru/award?keyword=bardoli+satyagraha+pdf
    • https://cdn-cms.f-static.net/uploads/4388428/normal_5fe9ab789ffdc.pdf
    • https://bowetupivivuz.weebly.com/uploads/1/3/1/4/131437724/f2990428.pdf
    • https://cdn-cms.f-static.net/uploads/4461484/normal_5fd11c5e97789.pdf
    • https://cdn-cms.f-static.net/uploads/4475208/normal_605a78882c494.pdf
    • https://momukilogavar.weebly.com/uploads/1/3/1/4/131437465/7090903.pdf
    • https://static.s123-cdn-static.com/uploads/4374022/normal_5fed67a013a8a.pdf
    • https://kegozorud.weebly.com/uploads/1/3/0/7/130740561/tinatotabugaj-wetin-betewopej.pdf
    • https://tawugeri.weebly.com/uploads/1/3/4/7/134774142/9828930.pdf
    • https://rowusebejaron.weebly.com/uploads/1/3/1/6/131637242/7930986.pdf
    • https://cdn-cms.f-static.net/uploads/4489264/normal_5fd7cb3dba39b.pdf
    • https://static.s123-cdn-static.com/uploads/4473410/normal_60072f2b520cc.pdf
    • https://cdn-cms.f-static.net/uploads/4419192/normal_5fe9c8455d814.pdf
    • https://fepunasavejupab.weebly.com/uploads/1/3/1/3/131381111/ea413fea223.pdf
    • https://tibijipobarak.weebly.com/uploads/1/3/4/4/134493900/b2041e4223a9c.pdf
    • https://cdn-cms.f-static.net/uploads/4380209/normal_60270287c928f.pdf
    • https://karopudalel.weebly.com/uploads/1/3/4/8/134881347/mokoxuga_rezezilo_pazuvadiz.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/afee2b72-aba4-4690-a218-ae2347d8a9e0/mefevegujufufadukilud.pdf
    • https://s3.amazonaws.com/nitajosasa/median_nerve_formation_and_course.pdf
    • https://s3.amazonaws.com/gurafoga/xeviwepe.pdf
    • https://s3.amazonaws.com/bubeto/detuzebefiziwopawe.pdf
    • https://uploads.strikinglycdn.com/files/744b428f-1060-49dc-856a-e998941d429e/85963477215.pdf
    • https://s3.amazonaws.com/sabobenuwe/jadepagamovagagegin.pdf
    • https://s3.amazonaws.com/wobuzisibal/siwolifawonas.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_off000117ad.bin
4f1141b4904991cde7ec6c680ef4d6ad5e29a058d0b18a15eeca2d208a8f6d7f
pdf-font-stream PDF embedded font (sfnt) at offset 0x117AD 5456 bytes
font_01_sfnt_off00012a3f.bin
cd8fe735b84c2e6023d20736661a5647d171e286b57b528c5f8f5e46c87b3dc5
pdf-font-stream PDF embedded font (sfnt) at offset 0x12A3F 11028 bytes