Malicious PDF — malware analysis report

Static analysis result for SHA-256 e67d5b3485923ac9…

MALICIOUS

PDF

80.7 KB Created: 2021-08-18 17:52:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b23d81b32b56a1d8db019fd333edf644 SHA-1: eb941e49cbbb0f2027f40aee47a5b1e929ed259e SHA-256: e67d5b3485923ac9cfd35032a899ba96a49b285707a341ab4d13fc8c4ec092f1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF document was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as a phishing trojan. It contains numerous links pointing to external websites, many of which are hosted on compromised CMS upload directories, suggesting a link farm designed to redirect users to malicious content. The document body is heavily obfuscated and unreadable, indicating an attempt to hide its true purpose.

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 http://startmatbaa.com/userfiles/file/sajobejopozuririlozubas.pdf
    • http://neuragen.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1609e2c43c7de6---46818379385.pdf
    • http://www.psstrecno.sk/wp-content/plugins/formcraft/file-upload/server/content/files/1608353159bdf7---zagesasapefibawofe.pdf
    • https://utilitydiscount.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ba6cd71a95c---moriwatatetosaganowibufov.pdf
    • https://tfnd.org/wp-content/plugins/super-forms/uploads/php/files/84dd796476c9036fb0cac1aea0ce5d32/81265661520.pdf
    • http://gizmakina.com/depo/sayfaresim/file/95282259062.pdf
    • http://sevimticaret.net/userfiles/file/64099128150.pdf
    • http://dataprint.ie/uploads/file/7444518677.pdf
    • http://www.asap-recruitment.net/upload/file/sexiputu.pdf
    • http://katachizu.com/img/news/files/16780931216.pdf
    • https://ncfouting.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ebd8ba7235---90903650906.pdf
    • http://allamericannursing.com/userfiles/file/pikasewu.pdf
    • http://shsuorui.com/uploadfiles/fckeditor/20210719/file/16266679162084.pdf
    • https://www.partyshuttlebus.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1608de6175872d---79802205891.pdf
    • http://ark-mr.com/data/home/qxu2063190031/htdocs/uploadfile/files/kumala.pdf
    • https://cengilli.com/icerik_images/file/pokodidemejifi.pdf
    • http://dagmare.de/userfiles/file/duzaxagajurorisob.pdf
    • http://sportgalaktik.sk/userfiles/file/rexoneladatekegazixexisux.pdf
    • http://klinok-saintp.ru/files/74630151371.pdf
    • https://laihouston.com/wp-content/plugins/super-forms/uploads/php/files/bc1bd4b642abe37e411e88eee64f702e/52847705309.pdf
    • https://rffsev.ru/wp-content/plugins/super-forms/uploads/php/files/600fc05bad60faa9df2cd254ef5ba777/xomuramopozarupofexef.pdf
    • https://www.kngroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608882862eb31---zuxewajuzajumowuno.pdf
    • http://wksystems.net/HotelEstimator/userfiles/file/74923386888.pdf
    • http://www.stratcareerservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084767e53d3d---dovovejowip.pdf
    • http://asesorgubernamental.com/images/file/rulut.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=phantom+of+the+opera+piano+duet+sheet+music
    • 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_off0000d7b7.bin
fffbf18926b6d04c00c3dfdef31c085b0734179477dc5a22af0fbf0ec7245dae
pdf-font-stream PDF embedded font (sfnt) at offset 0xD7B7 16796 bytes
font_01_sfnt_off00010381.bin
db338b14381b4d611af95de49b4ecdf03981d016878b123220c5925961d198b0
pdf-font-stream PDF embedded font (sfnt) at offset 0x10381 10940 bytes
font_02_sfnt_off00011cac.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11CAC 16792 bytes