Malicious PDF — malware analysis report

Static analysis result for SHA-256 e41c02040c5d16e3…

MALICIOUS

PDF

93.3 KB Created: 2021-04-04 18:46:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-12
MD5: 9c91031850534283d8218ef89971b9b1 SHA-1: 6716199ec13b6c6bd7cd8299ffd1691787c4f551 SHA-256: e41c02040c5d16e3856ecab0865f2ceca414967dbdbe7f5868b67e96f4c56c79
186 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, identified by the PDF_SEO_LINK_FARM and PDF_SEO_DISPOSABLE_LINK_FARM heuristics. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or distributing further malware. The embedded URLs suggest a strategy to manipulate search engine results or lead users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://kuzutuzo.ru/award?keyword=biografia+de+aristoteles+onassis+pdf PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4376601/normal_6029f38a4170d.pdfIn PDF document text
    • http://zimuzezu.22web.org/meditation_techniques_for_stress.pdfIn PDF document text
    • https://natagudere.weebly.com/uploads/1/3/4/5/134526504/8fd74c4e9f353.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4427282/normal_6023bb5fe46a6.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4444877/normal_60684bf8dde1c.pdfIn PDF document text
    • https://winulovovitazu.weebly.com/uploads/1/3/0/7/130740324/8268072.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4462341/normal_5fceaf6b8c1bd.pdfIn PDF document text
    • https://subamepowesita.weebly.com/uploads/1/3/4/8/134875458/pusevuwejeralo-fukere-joxerezefatas.pdfIn PDF document text
    • http://jaladonubitow.22web.org/27725068976.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4403418/normal_6032a001b14c8.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4413370/normal_6050006ca14d3.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4371247/normal_5fcb3f218ce8f.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4384295/normal_5ffdf8cc58104.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/tiniruru/7152740728.pdfIn PDF document text
    • http://kiwaxebaka.rf.gd/vakaso.pdfIn PDF document text
    • https://s3.amazonaws.com/leteraxewe/syngress_cissp_study_guide_3rd.pdfIn PDF document text
    • https://s3.amazonaws.com/wukevirenesu/tukuzejolinu.pdfIn PDF document text
    • http://jigolesapabinu.rf.gd/john_deere_48c_mower_deck_belt_size.pdfIn PDF document text
    • http://pavunununege.epizy.com/football_game_free_app.pdfIn PDF document text
    • https://s3.amazonaws.com/tidigudetefumof/94848880870.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00011155.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11155 5260 bytes
SHA-256: 5b81a0ccf5f552ea8400b13a7eb25c7960ce2496772c821f3b2c18376cee7d98
font_01_sfnt_off0001234a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1234A 14316 bytes
SHA-256: 91a4b814a5bbf57a913d7bbbd2421809b914cea0d8ad1c8d1e0986eb78936404
font_02_sfnt_off00015139.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15139 16060 bytes
SHA-256: 5b0d2701ab39d2f69c66d7d16c60d8db0b323aa0832947137e757b5401d27330