Malicious PDF — malware analysis report

Static analysis result for SHA-256 4bfb87cbae8bdacd…

MALICIOUS

PDF

71.9 KB Created: 2020-11-18 23:11:25 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 657d9c8e5f2108a4456329b5f3709973 SHA-1: 1a38b0a6d07b5599057e1c1e22d700d46d8c0051 SHA-256: 4bfb87cbae8bdacda5d3a1eb6195b8849630cf1f838c6635b2f24896cf59e9ea
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a phishing or malicious intent. The heuristic 'PDF_SEO_LINK_FARM' suggests the document contains a large number of external links, likely to manipulate search engine results or direct users to malicious sites. While no scripts were explicitly extracted, the PDF structure and embedded URLs point towards an attempt to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://traffset.ru/123?utm_term=yod+symbol+astrology
    • https://cdn-cms.f-static.net/uploads/4371004/normal_5f8c9ec7c782d.pdf
    • https://dutajidadu.weebly.com/uploads/1/3/4/7/134730474/tizedeniluxiz-gefowigujotubu-senunomikale.pdf
    • https://kunudixi.weebly.com/uploads/1/3/4/6/134667289/bopigazajifefam_wisovovuv_gisifejivuke.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/kotenu/report_abandoned_vehicle_in_san_jose_ca.pdf
    • https://s3.amazonaws.com/kizugokofo/zaduwuromidizulemajol.pdf
    • https://s3.amazonaws.com/zikeko/apologia_de_socrates.pdf
    • https://s3.amazonaws.com/votuweroxigezog/chaos_contemptor_dreadnought_rules.pdf
    • https://s3.amazonaws.com/tumasun/rerivabevuduramumuwa.pdf
    • https://s3.amazonaws.com/wixanarer/nick_godejohn_parents.pdf
    • https://uploads.strikinglycdn.com/files/02033434-40d6-429d-9381-dbff861320a1/51116961202.pdf
    • https://uploads.strikinglycdn.com/files/75a602e4-1905-4207-9310-bad31ed9efac/harry_potter_cosplay_slytherin.pdf
    • https://s3.amazonaws.com/zazelujeju/engagement_skills_trainer_2000_manual.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_off0000dcf5.bin
fca80f74f39bd913445d1dad2062718a609b10e24d8921ce0242797fa3df4aa0
pdf-font-stream PDF embedded font (sfnt) at offset 0xDCF5 5348 bytes
font_01_sfnt_off0000ef12.bin
21121a3deb7d857fe91f890e63a8154de950c802eeb5b2ce108805b5fedfca86
pdf-font-stream PDF embedded font (sfnt) at offset 0xEF12 10552 bytes