Malicious PDF — malware analysis report

Static analysis result for SHA-256 21050da6f8ef6198…

MALICIOUS

PDF

89.5 KB Created: 2021-08-09 07:56:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 5c22488e9598ceb189d54ef06a8c93f9 SHA-1: 293ca02e3c02ad77f31b5b77ddebbcd07f2df2f1 SHA-256: 21050da6f8ef619866995789e2116ba032bcb6a9de0ca634937540d8d6ce8ecf
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to compromised WordPress sites, identified by the 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' heuristics. The ML classifier and ClamAV detection strongly indicate malicious intent, with ClamAV specifically identifying it as 'Pdf.Phishing.Trojan'. The document body is heavily obfuscated and unreadable, but the presence of these link farms suggests a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1610d7bcda212c---73358768876.pdf
    • http://tv-sat.cz/userfiles/file/rojugibilebipe.pdf
    • http://strandedtattoo.net/file/19088773828.pdf
    • https://atlasautoglass.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608753ab5370c---zojezukazofelavikifetokiw.pdf
    • http://coutleelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/medino.pdf
    • https://www.acptechnologies.com/wp-content/plugins/formcraft/file-upload/server/content/files/160858c33e87c0---53737778622.pdf
    • http://amirafouad.com/uploaded_files/file/3908274163.pdf
    • http://clubchic.lv/c/i/files/sisaduximifovoxizakisi.pdf
    • https://qualitylightsolutions.com/wp-content/plugins/super-forms/uploads/php/files/897a3e47a2a07796e4695702aa1e5920/31078251032.pdf
    • https://www.sblending.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160a116b8668f0---bijurugumixufevewo.pdf
    • https://lea-inc.com/wp-content/plugins/super-forms/uploads/php/files/676e1c45acab16ba92340689f784849c/vebatanaxelefaw.pdf
    • https://bursac.net/userfiles/file/bomelevuvukasafinafi.pdf
    • http://zawayakw.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077c94e3f32b---44226847418.pdf
    • https://jodhpurtravels.com/nbloom/fckuploads/file/wupuvupodumedutobebu.pdf
    • http://brenna-ski.pl/userfiles/file/nojaka.pdf
    • http://accurateverdicts.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b8980c08232---83635282383.pdf
    • http://www.chinahkcarplate.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084bbcc7b79c---gupojajibupowosanawi.pdf
    • http://mas.vacations/wp-content/plugins/formcraft/file-upload/server/content/files/160f021a0eb077---44727784488.pdf
    • https://kicksomeglass.com/wp-content/plugins/super-forms/uploads/php/files/18116ba711ae7b09203dab981a451562/bitukovikudiparopudavemiw.pdf
    • http://maxgear.cz/webpagebuilder/ckfinder/userfiles/files/88270035391.pdf
    • http://claudiodauelsberg.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607901803aaee---73561777713.pdf
    • http://slp72.com/clients/7/7b/7b902bee17765b19ebdde6030f24742d/File/rijotabaf.pdf
    • https://www.perfumista.co.uk/wp-content/plugins/super-forms/uploads/php/files/5b8d55fb65128f671663142e414c607c/12313952337.pdf
    • http://bhsclassof70.com/clients/a/ac/acf0241a72c9eb28a719a759cf8a4748/File/zupopepexa.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=which+thrawn+book+to+read+first
    • 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_off0000f9a0.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF9A0 16792 bytes
font_01_sfnt_off000111b2.bin
9f14d181d9a49d25650c51260767ff6af872191130099e82b73a2ce974109cc9
pdf-font-stream PDF embedded font (sfnt) at offset 0x111B2 17056 bytes
font_02_sfnt_off00013daf.bin
ad1ff1ff00db42976cbd502df01e6fd9677b967e28f27607f3e136ec1f583d77
pdf-font-stream PDF embedded font (sfnt) at offset 0x13DAF 10840 bytes