Malicious PDF — malware analysis report

Static analysis result for SHA-256 8db4d1377ab9de1b…

MALICIOUS

PDF

58.5 KB Created: 2020-12-03 17:09:26 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 8b2e02174dc820377133393ece8e8fd7 SHA-1: 759440e845c7535115c826b4a31c8f65401b92a9 SHA-256: 8db4d1377ab9de1b19a17ddf01be5e6908cd130b35ca8bec0619b0eb93ffe29c
156 Risk Score

Malware Insights

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

The PDF contains a significant number of external links, with one heuristic specifically identifying a 'mass external PDF link farm'. The primary malicious URL identified is 'https://traffine.ru/strik?utm_term=combinatorics+worksheet+pdf', which is likely used for phishing or to host further malicious content. ClamAV and an ML classifier also flagged this PDF as malicious, indicating a high likelihood of malicious intent.

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://traffine.ru/strik?utm_term=combinatorics+worksheet+pdf
    • https://cdn-cms.f-static.net/uploads/4465269/normal_5fad5afdd2f3f.pdf
    • https://sijevunima.weebly.com/uploads/1/3/1/8/131859613/8a8b9ae25ba2.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/61afc700-560e-41cf-9a12-4051871c5ab5/la_guerre_de_troie_n_aura_pas_lieu_rsum.pdf
    • https://s3.amazonaws.com/domegagowevag/wetaduwub.pdf
    • https://uploads.strikinglycdn.com/files/0c005e49-5b4c-42cd-a49f-13909dfa8162/70680725275.pdf
    • https://uploads.strikinglycdn.com/files/09ab340c-c1c4-45b1-92f6-a2ba8a8e446e/cuantos_ejes_de_simetria_tiene_un_octgono.pdf
    • https://uploads.strikinglycdn.com/files/36fd0d51-8c6e-47b2-b637-deaa85387c0a/36575634634.pdf
    • https://s3.amazonaws.com/juvuraguvutoxif/read_allegiant_online.pdf
    • https://s3.amazonaws.com/mexesazaxasa/ayatan_sculpture_mission_guide.pdf
    • https://uploads.strikinglycdn.com/files/85c4bea0-952f-4b51-8df2-a11565c8fb8e/oru_murai_piranthen_oru_murai_piranthen_song_download.pdf
    • https://s3.amazonaws.com/vixuwogetiv/11770221895.pdf
    • https://s3.amazonaws.com/tesotiwapax/51305293131.pdf
    • https://s3.amazonaws.com/wukara/opioid_crisis_va.pdf
    • https://uploads.strikinglycdn.com/files/bf5adb54-f181-474a-8b0a-e004b1551780/93367816723.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_off0000aad8.bin
1f6048c797e40af3046278259bc378a3764c9bb37dfc9ee39cb13a317cebb958
pdf-font-stream PDF embedded font (sfnt) at offset 0xAAD8 5564 bytes
font_01_sfnt_off0000bda4.bin
ce5965f0a7f2c4620c59a8c60ce4b8457e4bbee4e6d832fec5c95ecb7a5a295a
pdf-font-stream PDF embedded font (sfnt) at offset 0xBDA4 9400 bytes