Malicious PDF — malware analysis report

Static analysis result for SHA-256 8a72555cc180f5d0…

MALICIOUS

PDF

72.5 KB Created: 2021-06-12 12:51:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 2f55b3f3955bd05f19ae3c3fdd38d01a SHA-1: 72f9a8cc3cc6f42bcf7d7c10f9cf36601ea80b9e SHA-256: 8a72555cc180f5d051d20d484632a333af2c17d5818cb00b024f2018b9242d7b
156 Risk Score

Malware Insights

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

This PDF file was flagged as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains a large number of external links, with the primary URL being 'https://irlanc.ru/pbw?utm_term=economics+paul+krugman+robin+wells+5th+edition+pdf', disguised as a search result for an economics textbook. The heuristic 'PDF_SEO_LINK_FARM' indicates the PDF is designed to host numerous links, likely for SEO manipulation or to distribute further malicious content.

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-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://irlanc.ru/pbw?utm_term=economics+paul+krugman+robin+wells+5th+edition+pdf
    • https://ponefapu.weebly.com/uploads/1/3/1/6/131637257/banepomit.pdf
    • https://cdn-cms.f-static.net/uploads/4488102/normal_6026c8be06385.pdf
    • https://cdn-cms.f-static.net/uploads/4392215/normal_602711c6a8f3b.pdf
    • https://cdn-cms.f-static.net/uploads/4387813/normal_5fdc2e4364d90.pdf
    • https://static.s123-cdn-static.com/uploads/4423442/normal_6005e65776f89.pdf
    • https://static.s123-cdn-static.com/uploads/4380871/normal_5fee34e3e7608.pdf
    • https://cdn-cms.f-static.net/uploads/4460460/normal_602d65892eb4a.pdf
    • https://cdn-cms.f-static.net/uploads/4368224/normal_605525dcab398.pdf
    • https://static.s123-cdn-static.com/uploads/4393485/normal_6002c5765f10b.pdf
    • https://cdn-cms.f-static.net/uploads/4486775/normal_60628a1620460.pdf
    • https://static.s123-cdn-static.com/uploads/4497372/normal_6008acd426d0b.pdf
    • https://static.s123-cdn-static.com/uploads/4460057/normal_5fcbd98b70348.pdf
    • https://static.s123-cdn-static.com/uploads/4459321/normal_6002720eea8c7.pdf
    • https://cdn-cms.f-static.net/uploads/4418362/normal_6065610a33640.pdf
    • https://cdn-cms.f-static.net/uploads/4407562/normal_601876cdeaf6b.pdf
    • https://jamelowo.weebly.com/uploads/1/3/1/6/131606155/1517204.pdf
    • https://static.s123-cdn-static.com/uploads/4446491/normal_5fe5b53314635.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/9d8cb04f-ced0-4aa4-99c5-40662d0ef049/tokavixikobirafado.pdf
    • https://uploads.strikinglycdn.com/files/169b1000-637f-48dc-83a5-38f54c88a741/atari_flashback_7_deluxe_game_list.pdf
    • https://uploads.strikinglycdn.com/files/3fb492f9-fd2c-442c-b73b-96a1074353d9/how_to_competency_based_interview.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_off0000d8ec.bin
2ff8840683a93df964f2e168e176900ae68c459ffaeb39568f66686390270c71
pdf-font-stream PDF embedded font (sfnt) at offset 0xD8EC 5944 bytes
font_01_sfnt_off0000ed15.bin
fdfe04ac17634f1ec3d558416a57e1069fc2f40832473d3c8c949038b3325ecd
pdf-font-stream PDF embedded font (sfnt) at offset 0xED15 10940 bytes