Malicious PDF — malware analysis report

Static analysis result for SHA-256 3f75f530a50effd3…

MALICIOUS

PDF

84.4 KB Created: 2021-09-16 07:19:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 560140659e43c9a1801fd6dd6ec12263 SHA-1: de22ff684d3ed10489d95c631722171a5b333518 SHA-256: 3f75f530a50effd3f97e55b2efcf3b6e9b57fb8ec3d7564db82a603609320544
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as malicious by ML classifiers and ClamAV. It functions as a link farm, containing numerous URLs pointing to various websites. Several of these URLs are hosted on compromised WordPress sites, suggesting a potential phishing or malware distribution scheme. The document body is heavily obfuscated and appears to be metadata from the wkhtmltopdf tool, rather than user-readable content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://smidgel.ru/uplcv?utm_term=how+to+save+webpage+as+pdf+on+ipad PDF link annotation
    • http://www.reroofingbrisbaneqld.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161337e7dc1de6---80648631741.pdfIn PDF document text
    • https://yptea.com/data/fckeditor/files/revebopekitafodarud.pdfIn PDF document text
    • http://friulanamarmi.it/images/file/99088723862.pdfIn PDF document text
    • http://printrun.nl/userfiles/files/jepokikusibosamafubal.pdfIn PDF document text
    • https://www.birdandwildlifeteam.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141f26dd1172---jamab.pdfIn PDF document text
    • https://kotypsy.pl/ckfinder/userfiles/files/28724970427.pdfIn PDF document text
    • http://luberoff.com/userfiles/file/93888694566.pdfIn PDF document text
    • http://asesorgubernamental.com/images/file/95631433875.pdfIn PDF document text
    • https://www.hotel-palladium.gr/wp-content/plugins/super-forms/uploads/php/files/gr1b8bp0ft9kpaekqj2t9cksqr/28338960001.pdfIn PDF document text
    • http://nepodoshlo.kz/ckfinder/userfiles/files/4812351111.pdfIn PDF document text
    • http://gvs-russia.ru/admin/ckfinder/userfiles/files/7850341672.pdfIn PDF document text
    • https://zohopinler.com/calisma2/files/uploads/26668230697.pdfIn PDF document text
    • https://musikkursus.dk/userfiles/file/wagimawonu.pdfIn PDF document text
    • http://andersonlawdecorah.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/furatemafavomojato.pdfIn PDF document text
    • http://elitaliaweb.it/upload/file/bixoneduf.pdfIn PDF document text
    • https://beautydiction.com/ckfinder/userfiles/files/28402601609.pdfIn PDF document text
    • https://sthouseluxury.com/upload/files/43339601763.pdfIn PDF document text
    • https://hitourkorea.com/FileData/ckfinder/files/20210903_5CCB51F319032BE6.pdfIn PDF document text
    • http://tecs4.com/intranet/ckfinder/userfiles/files/27615110123.pdfIn PDF document text
    • http://mardeestilos.es/fotos/file/paxujuzirukof.pdfIn PDF document text
    • https://rivieresoceanie.com/ckfinder/userfiles/files/47438731079.pdfIn PDF document text
    • https://ekoelprom.pl/public/images/editor/file/45681037710.pdfIn PDF document text
    • https://demo-calson.garment-pro.com/ckfinder/userfiles/files/togugewubojudunuzisab.pdfIn PDF document text
    • http://olympicburger1988.com/uploads/files/20232867994.pdfIn PDF document text
    • https://martan.es/cenavarra_userfiles/files/63164130334.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e512.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE512 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fd24.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD24 17700 bytes
SHA-256: 4b8e589b9ba45426e1fc9d1e2b679d74b507a1fcd6da2fa553f4cc61746222a5
font_02_sfnt_off00012b2d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12B2D 10808 bytes
SHA-256: b0cc1a8b51b3ae686319daa7065a96ee49e4547aa5fe56e4221d79216871d9bf