Malicious PDF — malware analysis report

Static analysis result for SHA-256 85bca721601a0fb0…

MALICIOUS

PDF

71.4 KB Created: 2021-07-12 22:53:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 218823be3b7df68a5aa18691569b5d8c SHA-1: d12703df86b62f081b8ba513721e57b817f0c040 SHA-256: 85bca721601a0fb0d1185131ae244d81c37b958ff15a97db84659c9244e5f5f6
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan payload. It contains a link farm pointing to multiple compromised WordPress sites, likely serving as a distribution point for further malicious content. The presence of embedded URLs and the nature of the heuristics suggest an attempt to redirect users to malicious resources, potentially for credential harvesting or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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://qboardapp.com/wp-content/plugins/super-forms/uploads/php/files/fcf69a99b1ced2aad33388a0d4ea1545/sejozujigumaw.pdf
    • http://www.heksan.com.pl/file/bikikigegenuderegojiros.pdf
    • https://unique.global/wp-content/plugins/super-forms/uploads/php/files/0c7dcf7aafdb77b3daf6fe0678ecaaff/38497796795.pdf
    • http://cameronhaddock.com/wp-content/plugins/formcraft/file-upload/server/content/files/160afc1b179bb8---guwusenatazijo.pdf
    • https://formapolis.it/wp-content/plugins/super-forms/uploads/php/files/9b36efa1a1c63f757b4b07e88c6b064b/80208921966.pdf
    • https://drahmetbostanci.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d7cca5a12b8---56558173264.pdf
    • http://acmemask.com/upfiles/editor/files/pifuzad.pdf
    • http://rilta.net/userfiles/files/fofuxidi.pdf
    • http://hasdeu.md/data/userfiles/files/niniripipifesa.pdf
    • http://www.grundys.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160a3df06ab54b---guwis.pdf
    • http://unseretochter.com/images/file/52219415218.pdf
    • https://yourtuscanyguide.com/wp-content/plugins/super-forms/uploads/php/files/a2deat64qq65808n9utug094j0/90112288070.pdf
    • https://njsolarpower.com/wp-content/plugins/super-forms/uploads/php/files/ec959f50f6991807168be29dbadd8494/34449905960.pdf
    • http://lordbeaverbrook1973.com/clients/76835/File/31163112407.pdf
    • http://bagandpack.ru/wp-content/plugins/super-forms/uploads/php/files/58d6130baf21da8345ad67d5bd8533fd/jazibivetalesuwulup.pdf
    • http://www.deadclan.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160c096bba7921---68874772438.pdf
    • http://progettarecasa.com/userfiles/files/fupugowuzerevuba.pdf
    • http://canadanur.com/resimler/files/67941146822.pdf
    • https://www.lightingsolutionsinc.net/wp-content/plugins/super-forms/uploads/php/files/4f68da06d2f889313130660317a4c0d9/kelumixivuzilomebajekiv.pdf
    • https://kes-stv.ru/wp-content/plugins/super-forms/uploads/php/files/65f305db80230eaf08a1f747ec7abad1/17596617140.pdf
    • https://ecowaytechnologies.com/ckfinder/userfiles/files/31840733848.pdf
    • http://terapie-psi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1609c30852e162---giwisokurogus.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=oxford+practice+grammar+advanced+with+answers+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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b488.bin
045bdee4f12606ad421659f2dfebb161a91a20ccd94ddd0491cd2467fb81a856
pdf-font-stream PDF embedded font (sfnt) at offset 0xB488 11300 bytes
font_01_sfnt_off0000cecd.bin
3145bae5312052d03fb1546681cbf21d64a8623492e5040381324cdf87d22ceb
pdf-font-stream PDF embedded font (sfnt) at offset 0xCECD 16156 bytes
font_02_sfnt_off0000f7f1.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF7F1 16792 bytes