Malicious PDF — malware analysis report

Static analysis result for SHA-256 4fdb8c73fcc82b5f…

MALICIOUS

PDF

83.7 KB Created: 2021-08-18 08:22:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 0769466a787faca1e51b8b690d6c6eb4 SHA-1: 257cd190338807056f28714ca7f6ce9b38fa809b SHA-256: 4fdb8c73fcc82b5fb68f79871f7811c05b8d322f1bb64a8b4a3b755837c55687
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as a phishing trojan. The document functions as a link farm, containing numerous URLs that point to various websites, including those hosted on compromised WordPress installations. The presence of 'utm_term' parameters in some URLs suggests an attempt to track user interactions, common in phishing campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://medvor.ru/uplcv?utm_term=predicate+nominative+and+predicate+adjective+ppt
    • http://golfvillageonline.com/userfiles/file/5181106385.pdf
    • http://www.chinahkcarplate.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f7d6963307e---30547776181.pdf
    • https://www.ediliziaindustriale.com/wp-content/plugins/formcraft/file-upload/server/content/files/16074c9272cb0a---83750786750.pdf
    • https://singaporeroadshow.com/wp-content/plugins/super-forms/uploads/php/files/c73dac51234470d6780b7f3b1891a65a/bubowafuvinalo.pdf
    • http://limoride.net/gallery/file/21807975385.pdf
    • http://getvisa.ru/images/File/73461278647.pdf
    • http://aal.tw/uploads/htmlupload/files/11254922670.pdf
    • https://mariellatriolo.it/public/file/94483850713.pdf
    • https://stpeterscbs.ca/ckfinder/userfiles/files/64995857266.pdf
    • http://cioccolatogallucci.it/userfiles/file/lekezoxak.pdf
    • http://chickendaylacrescenta.com/uploads/files/84711168382.pdf
    • https://adbetelparaguay.com/wp-content/plugins/super-forms/uploads/php/files/d7ee275a75b6b5b8b18e43c95ba9046b/wejajapuzulup.pdf
    • https://3dreamstudios.com/wp-content/plugins/super-forms/uploads/php/files/46f132bfab70d259e63cd2366d84a9ca/87439755850.pdf
    • http://stphilomenaonline.org/userfiles/file/29724918219.pdf
    • https://vegas-shop.net/uploads/files/kikivavoseguzipewizuno.pdf
    • https://graffitipaintstudio.com/wp-content/plugins/super-forms/uploads/php/files/23c4381da7123cf1ae1ec41c72650f67/14153641397.pdf
    • http://asirius.su/wp-content/plugins/super-forms/uploads/php/files/eff4db440cd143293d9002cf1c362b84/31201414952.pdf
    • http://studiodispirito.it/userfiles/file/19351654300.pdf
    • http://roocenter.ru/upload/file/9453449780.pdf
    • http://wilkinsconnection.com/clients/9/94/94ba1e7d864c5c8af3bb481f5f9f31de/File/kovesikilema.pdf
    • https://hotelritariccione.it/wp-content/plugins/formcraft/file-upload/server/content/files/1608b3ac6c4693---vogonusuwipagowa.pdf
    • http://elenasteele.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e415e9c137---nopemevez.pdf
    • https://www.idahomedia.com/wp-content/plugins/super-forms/uploads/php/files/f463828c7bcc9772883e2d46dfbb7d8f/xedut.pdf
    • http://chokmanee.com/userfiles/file/85588390686.pdf
    • http://yaqeen-eg.com/userfiles/file/gavexo.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_off0000e54b.bin
e8dd209767539fea7742098cf0301d483dcc6abde470081d309bb7bafbc7d4c1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE54B 16816 bytes
font_01_sfnt_off000110b2.bin
66c2ea3bba06ec8795003c42592a784bf42bc274199310aa2463bb23928c6e0b
pdf-font-stream PDF embedded font (sfnt) at offset 0x110B2 10660 bytes
font_02_sfnt_off0001290c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1290C 16792 bytes