Malicious PDF — malware analysis report

Static analysis result for SHA-256 510773ab49565774…

MALICIOUS

PDF

81.4 KB Created: 2021-09-02 08:51:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f7568c889ee90f597e3b7c4721862235 SHA-1: 52e2d1cffa2fd5d33b8ac3a696572f55ad6dd510 SHA-256: 510773ab495657744c5495d9606819ac4a0326d6461eaea830ba6d6f2099e784
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The ML classifier and ClamAV detection strongly indicate maliciousness. The PDF contains numerous embedded URLs, many pointing to compromised WordPress sites, suggesting it's part of a link farm designed to redirect users to malicious content. While no scripts were explicitly extracted, the nature of the embedded URLs and the 'link farm' heuristics point towards a phishing or malware distribution vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 https://pixomot.ru/uplcv?utm_term=muddy+hand+warmer+power+bank+instructions
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16079751ae718d---38903185040.pdf
    • http://soldresold.com/Shradhdha-Mehra/soldresold/final/ckeditorimage/files/48460743915.pdf
    • http://www.linkkorea.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/160832ed1f1b0a---75741824741.pdf
    • http://turar-mussin.com/userfiles/File/54019580319.pdf
    • http://cageart.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1607ddc26ccc3a---59950424869.pdf
    • http://shtaket46.ru/page_edit/_samples/userfiles/files/39834556074.pdf
    • http://www.impactit.in/ckfinder/userfiles/files/39125879242.pdf
    • https://aakritidigitals.com/userfiles/files/52201454163.pdf
    • http://spadhotel.com/basefile/spadhotelcom/files/rororoma.pdf
    • https://www.breastcancerfoundation.in/wp-content/plugins/super-forms/uploads/php/files/48715cf293945131504b3ce5abb01afe/70307646869.pdf
    • http://www.brennholz-heinlein.de/wp-content/plugins/formcraft/file-upload/server/content/files/160fac9e2c074b---gunemow.pdf
    • https://relaxbotanika.cz/ckfinder/userfiles/files/jirapisopexobigal.pdf
    • http://cw-cut.com/uploads/file/jirefepejidovatifiraw.pdf
    • http://sarahscupcakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f9861e349c---24247442854.pdf
    • https://avistravel.ro/userfiles/file/14462413116.pdf
    • http://parkwestresidences.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a327e14e164---75846211600.pdf
    • http://kiuanai.com/userfiles/file/dofutapo.pdf
    • http://bsp-oblspl.org/ckfinder/userfiles/files/fuseri.pdf
    • http://studioriboldi.eu/userfiles/files/77340788312.pdf
    • https://aihr-iadh.org/uploads/FCK_files/file/zipegumigogenotogi.pdf
    • http://beepost.vn/upload/userfiles/files/muxamoziza.pdf
    • http://trongtinpc.com/luutru/files/zexagudirul.pdf
    • http://yonseri.org/userfiles/files/basosurononatuzipox.pdf
    • http://www.champcaregivers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160eddf19408ff---51141985634.pdf
    • http://c2r-auto.com/uploadfiles/file/2021052701024273499.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_off0000d889.bin
9a4d13979fdeae3b31601901243315aebfcc83f8e445563e36f11166f4891a20
pdf-font-stream PDF embedded font (sfnt) at offset 0xD889 17488 bytes
font_01_sfnt_off00010573.bin
da856dd45ec20ed38b05c790d564a36a0574955d0217e76c7b35904dd5813bad
pdf-font-stream PDF embedded font (sfnt) at offset 0x10573 11256 bytes
font_02_sfnt_off00011f8b.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11F8B 16792 bytes