Malicious PDF — malware analysis report

Static analysis result for SHA-256 cefd6be7fe9c288e…

MALICIOUS

PDF

78.9 KB Created: 2021-03-24 23:34:11 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 581b6479aa22d69bf6ceea91d89a5b4a SHA-1: 771d58fa40e06d309a7af1f4af3481415c5d2421 SHA-256: cefd6be7fe9c288ea594ea99d3ab6aab6d462ba8eeaa40afed02c20223730276
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript T1203 Exploitation for Client Execution

This PDF file was identified as malicious by multiple heuristics and a machine learning classifier, with ClamAV detecting it as a phishing trojan. The file contains a large number of external links, suggesting it functions as a link farm or SEO spam document. The primary URL, https://ponafet.ru/strik, is likely used to distribute further malicious content or lead users to phishing sites. No scripts were extracted, but the presence of numerous external links and the overall structure strongly indicate a malicious intent to redirect users.

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://ponafet.ru/strik?utm_term=after+the+quake+monterey
    • https://cdn-cms.f-static.net/uploads/4415051/normal_60552e568dca4.pdf
    • https://cdn-cms.f-static.net/uploads/4371524/normal_604da8414c7d9.pdf
    • http://grenkasalo4.xyz/can_you_replace_ue_boom_batteryr06e0.pdf
    • https://cdn-cms.f-static.net/uploads/4451545/normal_6041794bd41e4.pdf
    • https://static.s123-cdn-static.com/uploads/4418566/normal_5feb7872efe59.pdf
    • http://themarkuzmusic.com/what_year_did_carry_on_my_wayward_son_come_out44g3n.pdf
    • https://cdn-cms.f-static.net/uploads/4369775/normal_603bf7d115bea.pdf
    • https://static.s123-cdn-static.com/uploads/4460057/normal_5ff95e40f1882.pdf
    • https://static.s123-cdn-static.com/uploads/4388282/normal_5ffa8d76cbc1e.pdf
    • https://cdn-cms.f-static.net/uploads/4381289/normal_602d0b77afbae.pdf
    • http://ottics.ru/bluetooth-adapter_fr_mixer17vfg.pdf
    • https://cdn-cms.f-static.net/uploads/4403804/normal_602df36ce92c4.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://www.daltonmaag.com/
    • https://uploads.strikinglycdn.com/files/b8015570-8543-4f88-8e4e-4d93cad5acfb/41938309272.pdf
    • https://09972071-4174-499b-90b1-de3619f59f53.filesusr.com/ugd/d1c05f_1c340425381148a79b5f1e2550e0905d.pdf?index=true
    • https://uploads.strikinglycdn.com/files/3c90b592-51f3-4446-be59-022e4a8f51e7/vivitar_dvr786hd_user_manual.pdf
    • https://uploads.strikinglycdn.com/files/85fb6381-7d10-4acd-9d23-a21389c4e05c/what_to_mix_with_crown_royal_vanilla.pdf
    • https://uploads.strikinglycdn.com/files/1f6d2e64-7627-4e9e-b5f2-46fddd0ae82f/mechanical_fe_review_course.pdf
    • https://68fdcf0a-b1f0-4758-9edf-48d2be6d990b.filesusr.com/ugd/ac51ce_1e45ec93c00b46e997e8f32c3fd74673.pdf?index=true
    • 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e966.bin
5e9fec24961f5b4999504983e1fb40de344fac075ce03b9ca878f3bdd165b731
pdf-font-stream PDF embedded font (sfnt) at offset 0xE966 4912 bytes
font_01_sfnt_off0000f9fe.bin
93a2c21b78f5bd7286a2df1c40466b577bfa1f35d27e9ee064e238e0a50dda4f
pdf-font-stream PDF embedded font (sfnt) at offset 0xF9FE 11420 bytes
font_02_sfnt_off00012056.bin
1062cd8ddf90f4344fa193b395386d5669df1a952e5759311ca261a71931f361
pdf-font-stream PDF embedded font (sfnt) at offset 0x12056 4324 bytes