Malicious PDF — malware analysis report

Static analysis result for SHA-256 d8544c504c3e2d93…

MALICIOUS

PDF

80.7 KB Created: 2021-07-05 11:02:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: 995334b50b35fb8a7175c049b7cf39a4 SHA-1: 4e3df3dbdd231ad893caf2f1aa1cbe6b9d80e470 SHA-256: d8544c504c3e2d93d88d2bc0341a161b15c78a915f1a8b09b27732764deea6a8
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external resources, many of which point to compromised WordPress sites hosting other PDFs. This behavior is indicative of a link farm designed to distribute malicious content or facilitate phishing attacks. The ML classifier and ClamAV detection strongly support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9950

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://agsposure.org/wp-content/plugins/super-forms/uploads/php/files/9d3b0fcd557ca68dcbcadcd90fb8c122/97469127707.pdf In PDF document text
    • http://maxitelt.no/wp-content/plugins/formcraft/file-upload/server/content/files/1606cb6fc27140---70242606011.pdfIn PDF document text
    • http://www.x454.com/wp-content/plugins/super-forms/uploads/php/files/b05u5jivi4vevaq5jlqs5pfc67/xasifavupupanejeju.pdfIn PDF document text
    • http://www.viksexteriors.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608eea7dcb38a---musudurozib.pdfIn PDF document text
    • https://www.landalastadservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084ed3e8de09---libevogogaluxagebipetarow.pdfIn PDF document text
    • https://globalazeri.az/wp-content/plugins/super-forms/uploads/php/files/1umjgf0h7qeka31lggvkbe57p5/luzevivasoru.pdfIn PDF document text
    • https://sandalyecenneti.com/wp-content/plugins/super-forms/uploads/php/files/afaiiluklf8t0tcr5a79jdt6bn/48060660040.pdfIn PDF document text
    • http://viaterrestre.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160926f3b13529---5400856658.pdfIn PDF document text
    • http://photographybynami.com/wp-content/plugins/formcraft/file-upload/server/content/files/16074cf19079a0---mosusexokeregudoxufokoguw.pdfIn PDF document text
    • https://nadinerogger.ch/userfiles/files/wamobaxevaminekodifufo.pdfIn PDF document text
    • http://youngshiny.com/userfiles/file/1624846901.pdfIn PDF document text
    • https://www.frankcapassoandsons.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086e8a9140ba---rarogososaparijenomejud.pdfIn PDF document text
    • https://hartwellcook.com/wp-content/plugins/super-forms/uploads/php/files/453dc4e2413c6c56ba3083f715c30f52/88405713635.pdfIn PDF document text
    • http://kovove-ploty-brany-zabradli.cz/UserFiles/File/wejidubuwi.pdfIn PDF document text
    • http://tks-forever.com/upload/2021/06/20/file/mamovisewizafubaxizirigar.pdfIn PDF document text
    • http://pulsrmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/160da8ea71f16b---melagaronikudovinasow.pdfIn PDF document text
    • http://www.theagentpipeline.com/wp-content/plugins/formcraft/file-upload/server/content/files/16096071d78693---vitasokaxas.pdfIn PDF document text
    • http://alptw.com/images/files/dibusamakavonanoj.pdfIn PDF document text
    • https://agmatbaa.com/upload/files/26474940449.pdfIn PDF document text
    • http://sazjah.com/wp-content/plugins/formcraft/file-upload/server/content/files/160958fce58da9---maxoxamobemovesudamok.pdfIn PDF document text
    • http://www.fullertherapy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160870e4a4b308---81494032931.pdfIn PDF document text
    • https://www.higher-energy-trampolineclub.com/wp-content/plugins/formcraft/file-upload/server/content/files/160be6e83d22d2---kemejobetufo.pdfIn PDF document text
    • http://shinex-auto.com/userfiles/file/fififupaduzujimebumufene.pdfIn PDF document text
    • https://advancedcheckcashadvance.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609f8a52e13e2---40435622563.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=carbonyl+chemistry+practice+problems+with+answers+pdfPDF 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_off0000d67b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD67B 17188 bytes
SHA-256: 78ec1c27033899663ec9d9be1840fefe17a0347551651283f49357aa02f04cf1
font_01_sfnt_off000102a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102A3 11256 bytes
SHA-256: afb45f554009261d095142d40d985386f72acc86a5a9de660285d01d9bb31976
font_02_sfnt_off00011cbd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CBD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1