Malicious PDF — malware analysis report

Static analysis result for SHA-256 4fa33787b5b444fb…

MALICIOUS

PDF

96.2 KB Created: 2021-07-04 22:54:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b3624a0222c83fb2c4d7b05c747e97d0 SHA-1: 2c53cf494e4db61a181b04da4e85fcd9518d2269 SHA-256: 4fa33787b5b444fbe85892e94bf797b875cb86eb288220ac58e4c50523f3f66b
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution. No scripts were extracted, and the document body was unreadable, but the URL structure and heuristic firings are sufficient to infer the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://osc-pribor.ru/products_pictures/file/xisuzimajuwevipamov.pdf
    • http://stevis.cz/files/file/fuwokegibixuzupifemawemim.pdf
    • https://ms02bet.com/contents//files/tuxadufisij.pdf
    • https://www.heainc.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609f5398ac922---bitokunoximufutopa.pdf
    • https://akita-inu.lv/www/files/files/ditogisuwaxowowe.pdf
    • https://alsterparkett.de/wp-content/plugins/super-forms/uploads/php/files/46oo49umrsk8la9jm4977eiblk/vewibarizagivexiwu.pdf
    • https://emprenderem.cl/files/49650749757.pdf
    • http://miamiwars.pl/wp-content/plugins/super-forms/uploads/php/files/b39db2936be3a59cc72129e22992c70f/gebuxapogusamojutunufipe.pdf
    • http://www.hptindia.com/wp-content/plugins/formcraft/file-upload/server/content/files/160717fd0d2af6---1976450204.pdf
    • http://lalitas-thaimassage-spa.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b700b2749db---11891787255.pdf
    • http://dabien.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/16098386e620e4---dubanokukosilofugisozu.pdf
    • https://lesartsdansmonjardin.com/userfiles/file/20210528075514.pdf
    • https://siphouse96.com/wp-content/plugins/super-forms/uploads/php/files/f53cda055272a96202cf643fe6d57eb5/niwax.pdf
    • https://twr1115.net/files/fckeditor/file/69933726152.pdf
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608a9498795f7.pdf
    • http://www.iso-clean.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160b2ae22c39aa---sakoforapovepuxuganusikam.pdf
    • https://haps.company/wp-content/plugins/super-forms/uploads/php/files/hashdif6l7s8rsd2iij98hlpu1/misaxajezufenowage.pdf
    • https://patriot.ch/wp-content/plugins/super-forms/uploads/php/files/mj03hj8ra5v6jpt8r6cit8u4h4/sozow.pdf
    • http://anatolianlgs.com/userfiles/file/14567317971.pdf
    • http://www.communityheroesproject.org/wp-content/plugins/formcraft/file-upload/server/content/files/160b7afcdc32a0---43778770844.pdf
    • https://www.carlosfunes.es/wp-content/plugins/formcraft/file-upload/server/content/files/160778eaa24765---60398274012.pdf
    • http://osullivanspressurewashing.com/wp-content/plugins/formcraft/file-upload/server/content/files/16074576e8475e---zumefelinerexavaxab.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=conquer+me+geneva+lee+read+online+free
    • 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_off000112fa.bin
04086045f8212b68b6cb1bb67268db0820434a33600ef9efdddc40a957661b95
pdf-font-stream PDF embedded font (sfnt) at offset 0x112FA 10772 bytes
font_01_sfnt_off00012b34.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12B34 16792 bytes
font_02_sfnt_off00014346.bin
c202e35a0b5bf8b3b5ad7c845ca160457fda1e3f8cc7a044454958cbcb2a37d3
pdf-font-stream PDF embedded font (sfnt) at offset 0x14346 18272 bytes