Malicious PDF — malware analysis report

Static analysis result for SHA-256 95caa8db06c3a16c…

MALICIOUS

PDF

85.0 KB Created: 2021-09-06 17:09:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 04eba6f65590471282564d02bd2532d9 SHA-1: f9e1e337b1e32cab7402f2b625d7445c6c414452 SHA-256: 95caa8db06c3a16ce7d339ebfb343cb413921cfae696e4b77aeab29bbb106df6
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as malicious by ClamAV and an ML classifier, with heuristics indicating embedded JavaScript and a link farm pointing to compromised WordPress upload storage and disposable hosting. The embedded JavaScript likely facilitates the download of a second-stage payload, and the link farm serves as a lure for users to access these malicious files, aligning with a phishing or credential harvesting attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://estoniapools.com/contents//files/sepakefito.pdf
    • https://hafa-verein.de/wp-content/plugins/super-forms/uploads/php/files/64dca02bcc599dfd0d9acda8e7e1e5a6/27145003418.pdf
    • https://sellerflows.com/wp-content/plugins/super-forms/uploads/php/files/84548896cb7f227cd8ed5bb3ee8743d8/zigudivanafuz.pdf
    • https://zzhqhi.com/d/files/21844888263.pdf
    • https://www.wikiwebagency.it/wp-content/plugins/super-forms/uploads/php/files/b8ba1487a8ac714434d754c191127358/nazewunozazomis.pdf
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/79e26674069e82eff3b195ad8e8bbd55/83677352841.pdf
    • http://autosvanbeek.nl/mindcms/js/ckf/userfiles/files/danow.pdf
    • https://hamzsabegi60szallo.hu/UserFiles/File/56112173833.pdf
    • http://www.vivelamusica.es/wp-content/plugins/formcraft/file-upload/server/content/files/160841c4a420a3---birij.pdf
    • http://tamker.hu/userfiles/file/27713744748.pdf
    • http://moscow-vernisage.com/files/files/52890323999.pdf
    • http://www.medic-pneumolog.ro/fisiere/file/zukewosapagez.pdf
    • https://bdata.vn/upload/files/sulutotasudetef.pdf
    • https://jagamimpi.org/contents//files/63017330095.pdf
    • https://lorenzonimmigrationlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b48418dacc---wasipodurada.pdf
    • http://aven.su/userfiles/file/walilutefafirefawawuwe.pdf
    • http://www.festivalmarrakech.info/wp-content/plugins/formcraft/file-upload/server/content/files/160875027991dc---24045193899.pdf
    • http://fence-alarm.com/userfiles/files/kepaxi.pdf
    • http://tramtronbetong.com/uploads/userfiles/file/1459066068.pdf
    • https://ilc.ua/wp-content/plugins/super-forms/uploads/php/files/0fvpr8k43vi2frqam5pv9r98v3/jobazuwezabakirapibopives.pdf
    • https://www.escon.it/wp-content/plugins/super-forms/uploads/php/files/0edbb759ce6fc3c47153055fa8f8c3e9/62020313611.pdf
    • http://osmed.cz/app/webroot/files/files/diduvedolamijuliwotimema.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=download+edx+certificate+as+pdf
    • 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_off0000e660.bin
8384c582ecf7ee904ead66002a18ced51e24866886b4c1bf46e529fa250350f2
pdf-font-stream PDF embedded font (sfnt) at offset 0xE660 10804 bytes
font_01_sfnt_off0000ff77.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFF77 16792 bytes
font_02_sfnt_off00011789.bin
2033f6d238ac6552d20700e76c9e8272c0e64d325e471e2d08547b95ec72dcd3
pdf-font-stream PDF embedded font (sfnt) at offset 0x11789 17932 bytes