Malicious PDF — malware analysis report

Static analysis result for SHA-256 bcb6f44153c1a1d7…

MALICIOUS

PDF

86.8 KB Created: 2021-06-28 00:21:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d9be0d51b1d2f3fff510e6d3affddef8 SHA-1: ec59b490f29263ee605ed885d57ee2c481091704 SHA-256: bcb6f44153c1a1d78064960c882af2d42188bbc1375db41a89162f9580737929
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The file contains numerous links pointing to compromised websites and potentially disposable domains, suggesting it's designed to lure users to malicious content. The presence of multiple distinct hosts and the use of 'utm_term' parameters in some URLs further support the link farm and potential phishing or malware distribution attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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 https://medvor.ru/uplcv?utm_term=apa+reference+if+no+author
    • http://geose.ru/userfiles/file/lapokar.pdf
    • http://xperion.hu/wp-content/plugins/super-forms/uploads/php/files/ea31241f2bae1d53a8dba5729017facb/70198386518.pdf
    • http://www.hollyskauaicondo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a7a37b4b06a---pijupikuxoweninudironopoj.pdf
    • http://zap-interactive.com/uploads/files/49643456580.pdf
    • https://www.focus.mu/wp-content/plugins/super-forms/uploads/php/files/4262969ac433f4d9024453617c4173d9/suxokelek.pdf
    • http://www.kliningstroy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160d2a071e613b---92713810520.pdf
    • https://sevsport.info/wp-content/plugins/super-forms/uploads/php/files/7840056b0ac55bdee6173158bba65c2c/47772535452.pdf
    • https://bringem.de/wp-content/plugins/super-forms/uploads/php/files/51649064ebb5694f3949342f953b67e3/18092977498.pdf
    • https://lerong.vn/wp-content/plugins/super-forms/uploads/php/files/a34f975dad979b84f62ceaabb04ba7de/negimegojigunapas.pdf
    • http://www.opencalgary.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a8316c348ee---zagakujimazifamapemobig.pdf
    • http://drstevealbrecht.com/wp-content/plugins/super-forms/uploads/php/files/5bae7f79ee3a60c0713987395d8f2bb6/latufalawaxi.pdf
    • http://raisemoneyonline.org/clients/6/69/691275cf9a36cab982b2498ebdc715be/File/negabalakuruvop.pdf
    • https://interesttour.com/wp-content/plugins/super-forms/uploads/php/files/3689e132407088d2f3e54b6751891157/29899289413.pdf
    • http://xn--h1aaebbkfib4a.xn--p1ai/sadm_files/sutarixegomenolawagi.pdf
    • http://dogable.de/userfiles/file/4322205978.pdf
    • https://maydongy.com/wp-content/plugins/super-forms/uploads/php/files/11bii2s99so3idsrlfl6ubsvcb/juminafudegojavigujoroxap.pdf
    • https://www.ideaklinik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1609971e62fd14---reguxikok.pdf
    • http://groupkaishan.com/d/files/15449059439.pdf
    • http://aaaexpressac.com/userfiles/file/kumobufiwegodevo.pdf
    • https://balance-global.com/wp-content/plugins/super-forms/uploads/php/files/2ml2dmcggvlgmvh8vbh1tn8mpe/79619091195.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_off0000f093.bin
61f70844f255e11deb3bc553d5c5a6fc9568ef392a0cfa32ad0ced9d4543b65a
pdf-font-stream PDF embedded font (sfnt) at offset 0xF093 17948 bytes
font_01_sfnt_off00011f0c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11F0C 16792 bytes
font_02_sfnt_off00013723.bin
3ffc4d14d8b9afae2ba77e17111f86a18b1f1d6f8eddd382d54814efaba7353e
pdf-font-stream PDF embedded font (sfnt) at offset 0x13723 10444 bytes