Malicious PDF — malware analysis report

Static analysis result for SHA-256 4f99df4920913bb5…

MALICIOUS

PDF

84.7 KB Created: 2021-07-02 11:20:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: eecd8076b6a9c364a2a683ec4a29ebd4 SHA-1: a946ce464beaa3108e7c1f1b040d407616745fa4 SHA-256: 4f99df4920913bb5a3d1fee38da5e04dc1af6626d6e5ce88a0924fec852b16ed
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document exhibits characteristics of a link farm, with numerous URLs pointing to compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. Although no scripts were directly extracted, the presence of embedded URLs and the link farm structure suggest the document is designed to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://studiogreenwich.ru/wp-content/plugins/super-forms/uploads/php/files/6797f4669cdb05e02806f4cdcd1c3765/19065208055.pdf
    • https://encouragingmath.com/wp-content/plugins/super-forms/uploads/php/files/1a435685e11bc2607c1b300ab747044c/29287561698.pdf
    • http://www.thebetterinsurance.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c619a39ec25---17892586553.pdf
    • http://cepsagibyachtfuels.com/images/photos/79914064200.pdf
    • https://comfortinnbarrie.com/phpsites/vertical_living/uploads/file/jugovaguxukologad.pdf
    • http://baliretreatcenter.com/olabali_ci/media/images/newsfiles/xezutosuwufilamalitazax.pdf
    • https://www.alongsideasia.com/wp-content/plugins/super-forms/uploads/php/files/47d6cf39b9311ab3ec91665f36649f02/fowezupimukokuwigon.pdf
    • https://prawobrzeze.info/userfiles/file/lowava.pdf
    • https://tungqibiotech.com/upfiles/editor/files/32559504795.pdf
    • https://propbrains.com/wp-content/plugins/super-forms/uploads/php/files/4187cb602fa38bdf2d661bb470e8605f/25859796572.pdf
    • https://www.deuba.info/wp-content/plugins/super-forms/uploads/php/files/i6n547j0rsgc0lpq0gpvgl4rn6/berekozodele.pdf
    • http://osullivanspressurewashing.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a681d723d2f---wamofaredoforeri.pdf
    • http://euro-ex.com/gukugaruvobaxodebigum.pdf
    • http://www.predia.cz/userfiles/file/17798199021.pdf
    • https://xn--22ck6bdp5cach0mc23a.com/ckfinder/userfiles/files/72325527458.pdf
    • https://www.davidwoodpersonnel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a7b7cc62008---80601523495.pdf
    • https://alternativecarrepair.com/userfiles/file/14197280145.pdf
    • https://davebakeragency.com/wp-content/plugins/super-forms/uploads/php/files/62c55b2722bc6f7320a7d419a3a60685/30052775492.pdf
    • http://penzionklara.cz/userfiles/file/15600615135.pdf
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/djlo62kej8fr275pdn5o7uugac/tazozozoxerijiguzoravoj.pdf
    • http://premiumresourcing.com/wp-content/plugins/formcraft/file-upload/server/content/files/160794ceb901d4---32762426862.pdf
    • http://projectbudapest.hu/wp-content/plugins/formcraft/file-upload/server/content/files/1607a5cd1c878b---96092943772.pdf
    • https://storage-in-motion.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078029a3330d---8881059604.pdf
    • https://www.marbelitesa.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160a9fa463e344---fefaxo.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=truth+table+of+2+bit+comparator
    • 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_off0000e74f.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE74F 16792 bytes
font_01_sfnt_off0000ff66.bin
0871514b4ebcb8471d6db6b17856f3472c514967643175546ed27dd1698bf59b
pdf-font-stream PDF embedded font (sfnt) at offset 0xFF66 10796 bytes
font_02_sfnt_off0001181b.bin
1cdb9e4da761539a5f935826b0319e07f65d53509cbd43bee2dedee09d58fb20
pdf-font-stream PDF embedded font (sfnt) at offset 0x1181B 17344 bytes