Malicious PDF — malware analysis report

Static analysis result for SHA-256 5a161508919bb84c…

MALICIOUS

PDF

89.7 KB Created: 2021-06-29 01:48:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: ab4114191e07bbe36c1afe59bcbf410c SHA-1: 97e4f99d539d0b968808a4ad8cb52294b5d2c12e SHA-256: 5a161508919bb84cac2f9e92e635377e3e17c356466a45c749f51ceffad97eb0
156 Risk Score

Malware Insights

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

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm pointing to compromised CMS uploads and disposable hosting, suggesting it's designed to redirect users to malicious sites. The presence of numerous unknown URLs further supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9924

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 https://www.bouldersudbury.org/wp-content/plugins/formcraft/file-upload/server/content/files/1608297b571b0c---xewaritel.pdf
    • https://ahi.com.ua/wp-content/plugins/super-forms/uploads/php/files/da81e995e5d193d16201f4eac4be261d/91370473372.pdf
    • https://hacunamatata.ru/wp-content/plugins/super-forms/uploads/php/files/4a7db9f4488e87af33cdfc7928c5b103/buwedivonaminux.pdf
    • https://baoholaodong24.com/userfiles/file/gudasabunagosodu.pdf
    • https://rffsev.ru/wp-content/plugins/super-forms/uploads/php/files/af5aebdb533d07aef4b06b1f048db0b2/2886446377.pdf
    • https://baodinhsolar.com/wp-content/plugins/super-forms/uploads/php/files/dc3fblklbc4n34klpdbv44lg72/kasuvewigejominodupij.pdf
    • https://whitelightdesign.com/wp-content/plugins/super-forms/uploads/php/files/fc832208e6bf1268bc37dd1118d010ac/punuxuwezu.pdf
    • http://timelessmebel.ru/wp-content/plugins/super-forms/uploads/php/files/f9c11df45323605e5b3c6c0e3c5e5d4f/migefuvapujiriwo.pdf
    • https://www.myjamaicais.com/wp-content/plugins/super-forms/uploads/php/files/2fc683a33977de5f3f14f3cc76ab4574/fogoluw.pdf
    • https://www.adler-leitishofen.de/wp-content/plugins/formcraft/file-upload/server/content/files/160ac55c9d167f---31350485721.pdf
    • https://oknoplus-omsk.ru/wp-content/plugins/super-forms/uploads/php/files/a0c3129ce3d61a114e674a21ebe0063f/71545391699.pdf
    • http://vipavtoufa.ru/wp-content/plugins/super-forms/uploads/php/files/305527d211a42b6ec2c192e607635f9e/silaruwujam.pdf
    • https://www.booster-p.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a14c77003c---54691886875.pdf
    • https://binhruamuinanobac.com/wp-content/plugins/super-forms/uploads/php/files/kabjiurg3f7e4vdq5al9sfa07l/wuxawe.pdf
    • http://charivne.info/images/file/kewupijutebel.pdf
    • http://cloverdiamond.com/file/mogokilibulupowuti.pdf
    • https://resonanceacteurs.nl/userfiles/file/judunovizenenazowape.pdf
    • https://heykidsletscook.info/wp-content/plugins/super-forms/uploads/php/files/7b850c44667f84f0003f2d6184e01ed8/63444832252.pdf
    • https://suprizpin.com/calisma2/files/uploads/66311383206.pdf
    • http://avtoarka.ru/wp-content/plugins/super-forms/uploads/php/files/1c20026215403bc396d803aac7a4f70f/potetureg.pdf
    • http://sfera-vlad.ru/img/file/1646627791.pdf
    • http://viaterrestre.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160bfe85caf6ac---notozakiman.pdf
    • https://apinero.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076f72b31381---dofogixu.pdf
    • http://ankurgroups.com/userfiles/file/pepimexateroba.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=miniature+and+precision+bearing+company
    • 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_off0000edf6.bin
1a494a11012a1f5c86437bf85589989da741de5e68630a8ef739103cbfa1103b
pdf-font-stream PDF embedded font (sfnt) at offset 0xEDF6 18876 bytes
font_01_sfnt_off00011eea.bin
9ca705f9ecb67a00853688c77763d216f397066ec152811422dc6b9ea2b2bf8e
pdf-font-stream PDF embedded font (sfnt) at offset 0x11EEA 1732 bytes
font_02_sfnt_off00012728.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12728 16792 bytes
font_03_sfnt_off00013f3f.bin
15e89dc60b27653ad68d19e59d19d09c1c44aea451111696d7d0411624075f7a
pdf-font-stream PDF embedded font (sfnt) at offset 0x13F3F 11156 bytes