Malicious PDF — malware analysis report

Static analysis result for SHA-256 4fc19eab223dcf99…

MALICIOUS

PDF

82.4 KB Created: 2021-09-20 04:03:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 27d2b3b4f61f018ddeec1b19580ab68f SHA-1: 94c5bc55d86ca56dc8c2385ac5e9942555dfd67f SHA-256: 4fc19eab223dcf997e01f816ea75ba007ab68ef95980a47ab3f3bc56ceed40be
156 Risk Score

Malware Insights

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

The PDF was flagged by ClamAV as Pdf.Phishing.Trojan and by an ML classifier as malicious. Heuristics indicate it functions as a link farm, with many embedded URLs pointing to compromised CMS uploads and disposable hosting domains. The document body is unreadable, but the overall structure and URL analysis strongly suggest a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/1612f0046bad3b---8041120631.pdf
    • http://globalfeedindustry.com/upload/files/tuwagamisajir.pdf
    • http://graczeonline.pl/userfiles/file/bewexevuwokaneg.pdf
    • http://www.valaisconsulting.ch/file/45340049808.pdf
    • https://pustelnik-budownictwo.pl/ckfinder/userfiles/files/ruzugapumusuwutodelifo.pdf
    • http://jan-fotografie.nl/upload/files/zonufudikilojadepubaxo.pdf
    • https://www.costaverde.it/wp-content/plugins/formcraft/file-upload/server/content/files/16142a6b1a223f---66488585064.pdf
    • http://ubytovani-budejovice.cz/picture/vtextu/file/fesogujodipaxuxafi.pdf
    • http://bebsulmare.com/userfiles/files/lejipuw.pdf
    • http://luxe-pools.fr/i/File/riwuvebavakapatigofo.pdf
    • http://pietrek.com/MARCUS/files/file/11404908230.pdf
    • http://esenkardeslerinsaat.com/resimlerfiles/pololujatunufotisamifur.pdf
    • http://szguilong.com/userfiles/files/92856662066.pdf
    • http://amexeuro.com/an3_Uploads/file/misunifuritovu.pdf
    • http://wedooverseas.com/userfiles/file/25979875330.pdf
    • https://postelezmasivu-praha.cz/ckfinder/userfiles/files/bidopititotizonudar.pdf
    • https://tpk-m.ru/files/file/ninosawenubinafajata.pdf
    • http://baominhlabors.com/upload/files/beviwe.pdf
    • https://phase1acoustics.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613450f59fc38---tivebakajun.pdf
    • https://tims.ro/ckfinder/userfiles/files/47485020078.pdf
    • http://szmchem.com/userfiles/file/9813649604.pdf
    • http://marta-galan.com/files/varios/file/wujekazuvekupirunudota.pdf
    • http://skrutit-probeg.ru/upload_picture/file/8622751200.pdf
    • http://aven.su/userfiles/file/depukekozurarigabufako.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=best+offline+audio+bible+app+for+android
    • 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_off0000dcc9.bin
6169b91471fc31e9b86538f950390a0d2a25de4d10167783492a669c25f22d3e
pdf-font-stream PDF embedded font (sfnt) at offset 0xDCC9 17940 bytes
font_01_sfnt_off00010ac4.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10AC4 16792 bytes
font_02_sfnt_off000122db.bin
faf6616671990506d6274809922a1d2fdb664a8384ede997e14829235dca3e3f
pdf-font-stream PDF embedded font (sfnt) at offset 0x122DB 10784 bytes