Malicious PDF — malware analysis report

Static analysis result for SHA-256 a23aef8da33cdeb3…

MALICIOUS

PDF

84.5 KB Created: 2021-07-07 18:15:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 2e2561fbebe39b91143fbc29f54afe22 SHA-1: 478bd56abfe4c78e54bcae8d3b3155efcbcbb11a SHA-256: a23aef8da33cdeb3f4694fb0e0745edc50850d4a27adec22cd2bf6d0e86a92e4
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to numerous URLs, many of which are hosted on compromised WordPress sites using the Super Forms plugin. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The primary function appears to be redirecting users to potentially malicious content via these numerous links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://alenakovalchuk.ru/wp-content/plugins/super-forms/uploads/php/files/5ef44529f48f194b3af57609eafccfc5/jekaxu.pdf
    • https://vinacomvietnam.vn/uploads/news_file/zagar.pdf
    • http://rahway1968.com/clients/5/53/53e48f2724afc57738bbbcfbfdbdad27/File/pinilezanoxoporepumuzuz.pdf
    • http://benhvientantao.com/img_duhoc/files/63951173450.pdf
    • http://chagatea.ru/wp-content/plugins/super-forms/uploads/php/files/8c2f734a84e5850d73104c0fa3800271/63458289377.pdf
    • http://reclaimsplus.com/wp-content/plugins/super-forms/uploads/php/files/388876dc2187a8548ab05449457e5a51/lanoritazevububigonanefo.pdf
    • https://www.freshstartdigitalmarketing.com/wp-content/plugins/super-forms/uploads/php/files/d7f1689100cb8a3638c25343fbb95815/giradili.pdf
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160786179778f3---66994007396.pdf
    • https://cafesca.mx/ckfinder/userfiles/files/83976781674.pdf
    • http://soldresold.com/Shradhdha-Mehra/soldresold/final/ckeditorimage/files/lidaxiduwigelusiwavitos.pdf
    • http://ceskylakros.cz/userfiles/file/defabepipelamolo.pdf
    • https://www.guestquesttravelmedia.com/wp-content/plugins/super-forms/uploads/php/files/niie7lp5br0kfq84u82oo6ifsd/44744502683.pdf
    • https://warungmimpishio.com/contents//files/95618385764.pdf
    • https://web-sila.ru/wp-content/plugins/super-forms/uploads/php/files/7814a5a86085abb026f03c4a49690915/belivudazevi.pdf
    • http://kath-kiga-bw.de/bilder/berichte/file/tikaxutunufasewuvewe.pdf
    • http://aprendanow.com/wp-content/plugins/super-forms/uploads/php/files/1bfed7783787e019a0bfd5449ab64eb2/rawufekifi.pdf
    • http://etkindenetim.com/resimler/files/sedekusebesudituwalop.pdf
    • http://adams-gold.ru/archive/image/file/32127755143.pdf
    • https://www.siemers-deutschmann.de/wp-content/plugins/super-forms/uploads/php/files/5fgdnta1p11kldsu7jg9d4n54i/82862408274.pdf
    • http://reclaimsplus.com/wp-content/plugins/super-forms/uploads/php/files/4a52eb367e4dd2b1c6adf6c20fe3d2fb/14431090450.pdf
    • http://trendybiz.in/usersfiles/file/rapotisewazofukopix.pdf
    • http://uspeh-kursk.ru/ckfinder/userfiles/files/vuduzater.pdf
    • https://abe-rdc.com/userfiles/file/naninalew.pdf
    • https://big-cash.de/wp-content/plugins/super-forms/uploads/php/files/5cip98s6abf8bvancpe85bn7fe/76006432927.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=abimelech+in+the+bible
    • 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_off0000eb71.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEB71 16792 bytes
font_01_sfnt_off00010388.bin
efebb6b3a47ee8a03feb814f7c1479607feff9fb3b6bd708f8aca63684b99e39
pdf-font-stream PDF embedded font (sfnt) at offset 0x10388 10068 bytes
font_02_sfnt_off000119b5.bin
e0a8fee967a464ac5559fdf403e52114573681ce56d8300fe9614238ff8908e0
pdf-font-stream PDF embedded font (sfnt) at offset 0x119B5 16560 bytes