Malicious PDF — malware analysis report

Static analysis result for SHA-256 13c4cac2e871e39c…

MALICIOUS

PDF

78.4 KB Created: 2021-08-11 11:31:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: ec034fe2aee7a6f70cf956607be571bb SHA-1: dad295c18964befc6125494e2c213c763f8c530e SHA-256: 13c4cac2e871e39cb31e7f3024dab662cbdb3df0ca863c110f7701e7c6297c76
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple compromised websites, as indicated by the 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' heuristics. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are indicative of a malicious document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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://jonkmp.nl/img/cms/file/gakew.pdf In PDF document text
    • https://twinslock.com/locktactyuma/userfiles/file/67311794154.pdfIn PDF document text
    • https://stakeoutllc.com/wp-content/plugins/super-forms/uploads/php/files/db9222dfc55d623a3ab7a21ccc18a3f0/sitebagirotidage.pdfIn PDF document text
    • http://svaz-podnikani.cz/files/file/pukozidodesew.pdfIn PDF document text
    • http://modern-pro.ru/files/file/sejutifo.pdfIn PDF document text
    • https://wodepcb.cn/uploadfiles/files/1530621337.pdfIn PDF document text
    • https://amrapalispot.com/userfiles/file/35630644594.pdfIn PDF document text
    • https://agsposure.org/wp-content/plugins/super-forms/uploads/php/files/2b9f8831ae580c5b2c87ff3b0b602bac/zadajewiripureteseri.pdfIn PDF document text
    • https://vico-domrep.com/ckfinder/userfiles/files/289660696.pdfIn PDF document text
    • https://www.penyembuhanholistikreiki.com/wp-content/plugins/formcraft/file-upload/server/content/files/16089381c40c49---bexaposatibib.pdfIn PDF document text
    • http://gptools.net/userfiles/file/kutozafedo.pdfIn PDF document text
    • https://mygoaltv.org/ipp/images/uploads/files/zuxebuxik.pdfIn PDF document text
    • http://lumieretvie.com/userfiles/file/2411424792.pdfIn PDF document text
    • http://2478.ru/admin/ckfinder/userfiles/files/ketoni.pdfIn PDF document text
    • http://belean.pl/userfiles/file/55488701368.pdfIn PDF document text
    • http://www.alex-vasilkov.ru/images/wisdom/file/biret.pdfIn PDF document text
    • http://makaifruits.com/wp-content/plugins/formcraft/file-upload/server/content/files/160baf28ab0b82---32079591105.pdfIn PDF document text
    • http://bertrandetgastineaudesigners.com/userfiles/file/kubiwap.pdfIn PDF document text
    • http://drironcat.com/images/file/48996167637.pdfIn PDF document text
    • http://handbook.hu/upload/page/file/voxawopasabexolo.pdfIn PDF document text
    • https://www.bouwenaaneensterkwerkgeversmerk.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160abcffa81177---66021787180.pdfIn PDF document text
    • https://grupahatak.pl/admin/_fck_files/file/bavisobuxekewod.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=atomic+structure+2+worksheet+answersPDF 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_off0000cb6f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB6F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e381.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE381 18564 bytes
SHA-256: 30c7938b00f833f30feb7eb701b3a1788db052031e294e05c34428c78cf0be0a
font_02_sfnt_off0001124d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1124D 10828 bytes
SHA-256: ca7e619b640ff1da7099a0fc2257cdbba24cd9b975b594c516f1e4815d036269