Malicious PDF — malware analysis report

Static analysis result for SHA-256 949134a8f4a62d62…

MALICIOUS

PDF

78.6 KB Created: 2021-09-16 20:27:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: cfcfa33a080bdd6a6c321d56ab7e0805 SHA-1: 0712cf0e774e0e18adbcdac40c6db660dbcf78e2 SHA-256: 949134a8f4a62d627ce0a4604b73979a54945c58a6add0a1ef706749296fadbd
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ML classifiers and ClamAV as malicious, exhibiting characteristics of a link farm. Several heuristics indicate the use of compromised CMS uploads and disposable hosting for hosting PDF files, suggesting a distribution mechanism for malicious content. Although no scripts were directly extracted, the nature of the links and the detection suggest it may lead to further malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 http://businessdevelopmentcenter.pl/uploads/userfiles/files/91691856051.pdf In PDF document text
    • http://zensushidanapoint.com/uploads/files/9027287846.pdfIn PDF document text
    • http://cedule-plachty.cz/files/file/fokupowuzuk.pdfIn PDF document text
    • https://doctmcooper.com/userfiles/files/87494281610.pdfIn PDF document text
    • http://szermgrt.hu/uploads/ckfinder/userfiles/files/72609043969.pdfIn PDF document text
    • http://thechitay.com/uploads/userfiles/file/2086416672.pdfIn PDF document text
    • https://hahapediatric.com/uploads/files/202109092337242838.pdfIn PDF document text
    • https://hippodrome-compiegne.fr/www/uploads/file/solefiroku.pdfIn PDF document text
    • https://groupekheidri.com/ckfinder/userfiles/files/jipimigixoxuj.pdfIn PDF document text
    • https://equalitas.es/userfiles/file/marebul.pdfIn PDF document text
    • http://wdnederland.nl/file/jokuzuditafapaneze.pdfIn PDF document text
    • http://kbautotech.com/board/datafiles/imagefile/63716129576.pdfIn PDF document text
    • https://ddriu.hu/wp-content/plugins/super-forms/uploads/php/files/2370b16fd378789f62e0bee785fe8340/fuvepuzexusiki.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a086e55cf8---26556500114.pdfIn PDF document text
    • https://bharatiyabhashaparishad.org/ckfinder/userfiles/files/dagogiris.pdfIn PDF document text
    • http://falegnameriacastiglione.it/userfiles/files/xetomawibuvejinid.pdfIn PDF document text
    • http://tuttotop.com/userfiles/files/darifuxelagexu.pdfIn PDF document text
    • http://conwaychristian.org/wp-content/plugins/formcraft/file-upload/server/content/files/1613836992ff4b---9340766420.pdfIn PDF document text
    • http://olympusflights.com/files/files/39518535770.pdfIn PDF document text
    • http://color-gateway.com/userfiles/file/pikosilirebugasagukukexis.pdfIn PDF document text
    • http://marinaxaraes.com.br/ckfinder/userfiles/files/nesejemep.pdfIn PDF document text
    • https://organicearthfiji.com/documents/file/49203706145.pdfIn PDF document text
    • http://marklaliberte.com/fckupload/file/furunolitutig.pdfIn PDF document text
    • https://fiscconsulting.com/userfiles/file/buforufiserasobudatuto.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=dirty+dinosaur+jokes+for+adultsPDF link annotation
    • 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_off0000cfbb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCFBB 10784 bytes
SHA-256: da0157647bec9f173ded399c2a2f40966821a8228e7833f2e81bd61d595b52e0
font_01_sfnt_off0000e8b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8B0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000100c2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100C2 17028 bytes
SHA-256: 05a1c5406ea7ae16541e38e8efa5e43df8ec5fccd6b3208a24333a46f2b0541c