Malicious PDF — malware analysis report

Static analysis result for SHA-256 b1f4499420a0b04e…

MALICIOUS

PDF

73.8 KB Created: 2021-06-29 06:17:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 6892489ba554451237901d447fc06602 SHA-1: 5f3be63bdf3dad7a708e33625485e99d6e019fa2 SHA-256: b1f4499420a0b04eaac754ec9095e2ee129004950dc256dfd2a70339680f053a
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple distinct hosts, many of which appear to be compromised CMS upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent. The primary function appears to be redirecting users to external sites, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://hncastlecable.com/d/files/90921229509.pdf
    • https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/aee9d7939c31c829d679a19c772fe019/vetiximivinomulalid.pdf
    • https://baongochoa.com/upload/file/bopifif.pdf
    • https://realimpacto.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160797b49d47ec---mubenukekumipupakobonaxe.pdf
    • http://msslink.ru/userfiles/files/82602531379.pdf
    • http://www.siscard.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3f25f3cb1c---karewetemopus.pdf
    • http://diysmart.net/userfiles/file/pekiwutujawokija.pdf
    • http://camionespanamericana.com/userfiles/file/weruzudaroral.pdf
    • https://dsodrecital.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608976d18050f---41482786774.pdf
    • http://postelezmasivu-brno.com/ckfinder/userfiles/files/posid.pdf
    • https://www.numberoneporthill.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160b7d1abd7e8f---31908761446.pdf
    • https://relaxationplusmn.com/wp-content/plugins/super-forms/uploads/php/files/cf4fff358fe758a44a0a55296d2d993d/lilomifolimonezenetefa.pdf
    • http://abpaluso.com/upload/file/biforomavuworowugitotekoj.pdf
    • https://singaporeroadshow.com/wp-content/plugins/super-forms/uploads/php/files/8caa93e5a4e1c97822e36e906cdb7d43/15266149626.pdf
    • http://www.radiopopiatej.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608cad13ddc3a---93947087228.pdf
    • http://www.pilonidalsinus.gen.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16083c0d643210---12867787520.pdf
    • http://totaleclipsenv.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c76d78def7---15531883137.pdf
    • https://joefairless.com/wp-content/plugins/super-forms/uploads/php/files/3d879202b2fe631f8cb60232f38c81b9/vowurevarutapesivalame.pdf
    • http://muskogeeroughers1967.com/clients/9/98/9899c641331876fb313f08ec475a0443/File/meruzetuwinakenixorakuk.pdf
    • http://pavcargo.ru/wp-content/plugins/super-forms/uploads/php/files/64920c29b4e6057f87baae77312d8f65/dudakibilupuzurovukixo.pdf
    • http://3handseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608220a81ee70---40826148110.pdf
    • https://emauto.lv/index/images/up/file/bubidiza.pdf
    • http://kulturazebrak.cz/userfiles/49290556208.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=difference+of+cubes+formula
    • 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000bf4a.bin
af42473483d308411f2c77290e56bf216e3649f0c8d730cf218f32b2d2e4f5f1
pdf-font-stream PDF embedded font (sfnt) at offset 0xBF4A 10640 bytes
font_01_sfnt_off0000d79d.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD79D 16792 bytes
font_02_sfnt_off0000efaf.bin
5f56909e726031eaaf82c7717d94ae3e18088c61bfff5ff0f083daa8201892bc
pdf-font-stream PDF embedded font (sfnt) at offset 0xEFAF 16276 bytes