Malicious PDF — malware analysis report

Static analysis result for SHA-256 4c280e4fa01f4f63…

MALICIOUS

PDF

119.5 KB Created: 2021-07-20 20:22:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a94450c849a05824155c847775fdab67 SHA-1: b12bb90f6b7f4171b270196b97d37550c57f9166 SHA-256: 4c280e4fa01f4f6307a7cabc8df325445c861e344e4752bf4da0e8d33ae2095b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution via these links. The document body is heavily obfuscated and unreadable, providing no direct content-based clues.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9931

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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 http://tokyoto.pl/UserFiles/file/22589436488.pdf
    • https://cald-lighting.com/wp-content/plugins/super-forms/uploads/php/files/a9958dd21d0057876461999f4992ef00/46133689644.pdf
    • http://3q1p.com/upload/file/2106300035101718771zd15ekuj816.pdf
    • http://antik-cafe-bergen.de/wp-content/plugins/formcraft/file-upload/server/content/files/16072da7d495a1---guxafipusekajixager.pdf
    • http://www.look4job.gr/images/_user_na/file/48508745450.pdf
    • https://nuregio.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608413fedd03b---gideliromibazume.pdf
    • http://perfectthesale.com/wp-content/plugins/formcraft/file-upload/server/content/files/160831f3f9545b---pubalej.pdf
    • http://www.advokat.com/app/webroot/img/fck/file/39144109657.pdf
    • https://alphacleanwashing.com/wp-content/plugins/super-forms/uploads/php/files/470b8e1f679d5b465c125c51d0285459/pamize.pdf
    • https://my-natural-style.net/upload/files/86368566438.pdf
    • https://echipamente-scule.ro/userfiles/file/6066078497.pdf
    • https://alphacleanwashing.com/wp-content/plugins/super-forms/uploads/php/files/af071e75265f882bd900b7175db151d8/86033337036.pdf
    • https://alenakovalchuk.ru/wp-content/plugins/super-forms/uploads/php/files/6a87b99afa968357194f077bb4212295/nosaxuzojolevowu.pdf
    • http://sdds.be/userfiles/file/54096955585.pdf
    • https://www.sussexweddingservices.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160b8476fafcb7---35871892.pdf
    • http://thanhlamresort.vn/wp-content/plugins/formcraft/file-upload/server/content/files/1609af8d337720---fosizezuribejero.pdf
    • https://coachtourbusrental.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d2cf2d425d6---kivupanakawuwopik.pdf
    • http://www.benvenutialmare.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084fe170eb45---25273486738.pdf
    • https://aquariumfargo.com/wp-content/plugins/super-forms/uploads/php/files/96a8e16274dd5738b5f346907bb64f1a/15812797662.pdf
    • https://windsbs.biz/files/file/38662851035.pdf
    • https://anmimar.com/royal/userfiles/file/ketimefowi.pdf
    • http://sculecuacumulator.ro/app/webroot/files/userfiles/files/dafadusu.pdf
    • https://www.amiunaorchestra.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160bef73449622---83898720151.pdf
    • http://dribblebar.pl/userfiles/file/daladezagaf.pdf
    • https://www.infrascale.com/wp-content/plugins/super-forms/uploads/php/files/480615fa34a582487f56758c33b32b7e/zuleda.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=html+header+content+type+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://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00014e2d.bin
0d3c5cc9733704eba255e7a508f6395045b0304a7ed047d863fb51835bfe6a38
pdf-font-stream PDF embedded font (sfnt) at offset 0x14E2D 20080 bytes
font_01_sfnt_off0001817c.bin
c489b032fcec64d55244b6d59ed2476d29e4dc11a6f85800c28d959ed8bd3524
pdf-font-stream PDF embedded font (sfnt) at offset 0x1817C 9108 bytes
font_02_sfnt_off00019faf.bin
7ce72a552caaf5d7376c4ebdbe1008b8fc8e22552b7ffe0fe568479c7751b0b0
pdf-font-stream PDF embedded font (sfnt) at offset 0x19FAF 10728 bytes
font_03_sfnt_off0001b816.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1B816 16792 bytes