Malicious PDF — malware analysis report

Static analysis result for SHA-256 c99fdf8ec6698dac…

MALICIOUS

PDF

80.4 KB Created: 2021-06-28 15:08:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 552e4ac47ef92fc10dd1af17ba5b5516 SHA-1: 92aaf8d46db72b192e52c25a89a5ece22daf4726 SHA-256: c99fdf8ec6698dacc1d1791cb206ce828850f50a9238c91e4637a1b147254f4e
156 Risk Score

Malware Insights

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

This PDF file was identified as malicious by multiple heuristics and an ML classifier. It contains a link farm pointing to numerous compromised WordPress sites and disposable hosting, suggesting an attempt to distribute malware or conduct phishing. The document body is heavily obfuscated and unreadable, providing no further context on its specific lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://rffsev.ru/wp-content/plugins/super-forms/uploads/php/files/e987e7aeb11ce243676d36f901fb9ced/5164056623.pdf
    • http://www.louthadventures.ie/wp-content/plugins/formcraft/file-upload/server/content/files/1607d89da67b52---voralakaxazaxomete.pdf
    • http://ajisushionline.com/uploads/files/70958214701.pdf
    • http://31kouqiang.com/userfiles/file/1624497598.pdf
    • https://acronimocostanzo.com/userfiles/file/tudoza.pdf
    • http://www.whirlpool-beachcomber.at/wp-content/plugins/formcraft/file-upload/server/content/files/16091fbb48d779---95083546827.pdf
    • https://arizonalightingsales.com/wp-content/plugins/super-forms/uploads/php/files/17e32f907b9ece3a8c2c4e2747acc905/47629098126.pdf
    • https://swotin.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a0f7843c67a---23962353929.pdf
    • https://bedandbreakfastchia.it/userfiles/file/kuditeselosi.pdf
    • http://rhodeislandalpha.com/clients/56223/File/lijafubejuwizifevivil.pdf
    • http://www.marsagri.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c4cbcb25d3c---kuguban.pdf
    • http://www.christinemartin.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160be859a93ddd---zisekuri.pdf
    • https://doitsolutions.co/wp-content/plugins/super-forms/uploads/php/files/9457f6e57f463990a2fe271ab188affe/nepolenomaxona.pdf
    • https://oneremote.ru/wp-content/plugins/super-forms/uploads/php/files/5c78516f2b3ebb942be05efe8b6fcc1d/53903319706.pdf
    • http://www.esthemed.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160bc136153d47---22104797306.pdf
    • https://alfa-pechati.ru/wp-content/plugins/super-forms/uploads/php/files/7e8f56ff08717f9d7de9f105cebe0603/9428238628.pdf
    • https://www.generalutilities.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a7986125deb---xubawezojuzuxejekapibi.pdf
    • http://allaboutdowney.com/userimages/96315704827.pdf
    • http://chiengthai.com/file_media/file_image/file/7863067318.pdf
    • http://fenotropil.ru/userfiles/file/39183275369.pdf
    • https://atolab.it/wp-content/plugins/super-forms/uploads/php/files/bd5d1499950694f908bd4a9b98dd6733/19061713080.pdf
    • http://karthikeyanjayaram.com/userfiles/file/kagosujibukot.pdf
    • http://asbu.net/uploads/FCK_files/file/fanuvizu.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=on+screen+b2+workbook+and+grammar+book+answers
    • 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_off0000d303.bin
4041d5b6bd03380292f05359e50da097e05739bcec9cccef74db0cecd95ad885
pdf-font-stream PDF embedded font (sfnt) at offset 0xD303 18212 bytes
font_01_sfnt_off00010123.bin
70d37469dba434ceb1c4f101db5269b090819567920384c716189d6e3a3d73d2
pdf-font-stream PDF embedded font (sfnt) at offset 0x10123 10940 bytes
font_02_sfnt_off00011a72.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11A72 16792 bytes