Malicious PDF — malware analysis report

Static analysis result for SHA-256 8091f1a2d5047e60…

MALICIOUS

PDF

86.0 KB Created: 2021-07-06 00:37:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 91431ae7cf48ff3c916ee39314939a7c SHA-1: 079bd37f136b47968f60639355c0a5d161d1ddd8 SHA-256: 8091f1a2d5047e60a4dd72926bbc689355058b54e7a593e93188a6ecfb919d17
156 Risk Score

Malware Insights

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

The file was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier, indicating malicious intent. It contains numerous links pointing to compromised WordPress upload directories, suggesting a link farm used to distribute malicious content or redirect users to phishing sites. The PDF's structure and the presence of external links strongly suggest it's part of a phishing campaign, likely delivered as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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://coachtourbusrental.com/wp-content/plugins/formcraft/file-upload/server/content/files/160df7d6640629---34231650252.pdf
    • http://antik-cafe-bergen.de/wp-content/plugins/formcraft/file-upload/server/content/files/160d65bba9097b---28374775142.pdf
    • https://muzeumkonstancina.pl/attachments/file/79521355566.pdf
    • http://codemessaging.net/ckfinder/userfiles/files/56430355200.pdf
    • http://thebrownsfamilyreunion2008.com/clients/81208/File/81271975825.pdf
    • https://heykidsletscook.info/wp-content/plugins/super-forms/uploads/php/files/9c37f9af4c4df5fa0529c7547c8a4f22/lugobiboguzodudivogut.pdf
    • https://carthink.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607be91062cc9---suturugoxeg.pdf
    • https://remoteworkerclub.com/wp-content/plugins/super-forms/uploads/php/files/fb7235c61f596e982d5b918b9f731062/99463978465.pdf
    • http://www.pattyn360.com/upload/forum/files/51193514387.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160af9c58e11e6---xamuvovedigujeradanafenal.pdf
    • https://maggies-handmade.com/UserFiles/files/31681745911.pdf
    • http://se-ty.ru/uploads/userfiles/file/labexikebuguf.pdf
    • https://aquariumfargo.com/wp-content/plugins/super-forms/uploads/php/files/263d021b1094f16d578a9df2213d5b58/35760634718.pdf
    • http://clinicaveterinariagussago.com/userfiles/files/gubokovewuvimazij.pdf
    • https://www.qlsny.com/wp-content/plugins/super-forms/uploads/php/files/1ded823e048ba122a22f27b69e582344/lawixufotak.pdf
    • https://law.com.sg/wp-content/plugins/super-forms/uploads/php/files/f17917d3aa5490a5b5ae22fcb44275ec/58670119389.pdf
    • http://brilliantsolarpaneling.com/userfiles/file/nibafo.pdf
    • https://thehamptonsbloomington.com/wp-content/plugins/formcraft/file-upload/server/content/files/160721e0ce1a83---jeserijotuseza.pdf
    • https://trunglamdecor.com/uploads/userfiles/file/gafitimazezenoxabupejeno.pdf
    • https://xo-sound.ru/userfiles/file/52076774917.pdf
    • http://www.korayozelguvenlik.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607711f34104d---85540200723.pdf
    • http://iberryhomemade.com/userfiles/files/40446602077.pdf
    • http://macap.nl/app/webroot/files/userfiles/files/57213224032.pdf
    • https://www.shopveriamici.com/wp-content/plugins/super-forms/uploads/php/files/e8bq00eu83d9v1k2jf2u624l01/nusufixij.pdf
    • http://novaserv.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f16c3abb0d---80154064437.pdf
    • https://utilitydiscount.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073fc3992420---89651393305.pdf
    • https://begili.com/uploads/image/files/44612102502.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=ai+interview+questions
    • 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_off0000f079.bin
5daa51b41da6bad67d537dca23c084b708bee361c3517e85339d4f91c05c7b44
pdf-font-stream PDF embedded font (sfnt) at offset 0xF079 16592 bytes
font_01_sfnt_off00011b3e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11B3E 16792 bytes
font_02_sfnt_off00013355.bin
47c34e0175e7c589880beaf5ff87992a3630913a5ef86dca7b48638c3611ab83
pdf-font-stream PDF embedded font (sfnt) at offset 0x13355 10272 bytes