Malicious PDF — malware analysis report

Static analysis result for SHA-256 9289452a1c5c05f2…

MALICIOUS

PDF

92.2 KB Created: 2021-07-14 00:08:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 3bec14fced02aca6838130c0f6330b1c SHA-1: da7fc9540477251ccd2283861b77af55f8d6e70d SHA-256: 9289452a1c5c05f2db427bdd0996fc5d24f67f3de7b30c7bd9aae6826ef0a6a5
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous URLs pointing to compromised WordPress upload directories, suggesting an attempt to distribute further malicious content or redirect users to phishing sites. The document body is heavily obfuscated and contains metadata from wkhtmltopdf, but the primary malicious activity appears to be the embedded URLs.

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 http://www.petersmetalstitching.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16094d20d83f56---43210290962.pdf
    • http://hoitruyengiaocodocvietnam.com/uploads/image/files/zunumisapumadi.pdf
    • http://accessiblevehicleservices.com/userfiles/file/85752435071.pdf
    • https://kermanrooz.com/img/files/penizafopavikinenoti.pdf
    • https://ecotranslation.ca/upload/editor/file/moduxona.pdf
    • https://alyosserspneed.com/userfiles/files/72212798590.pdf
    • https://mkting.com.co/wp-content/plugins/super-forms/uploads/php/files/d3bcc974e88aac706abe6dc29e1d1917/59644724380.pdf
    • https://growyourmoney.in/userfiles/files/48935806621.pdf
    • http://radissonhoteltraining.com/userfiles/file/kikisupinetogi.pdf
    • http://indemo.pl/Image/files/bisupeb.pdf
    • http://grupogmec.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bd77385367b---34171580223.pdf
    • http://rusiuojigalvoji.lt/wp-content/plugins/formcraft/file-upload/server/content/files/1609b75f83f5f8---21748915000.pdf
    • https://triangle-electronics.com/assets/userfiles/file/28138244802.pdf
    • https://cargobull.cz/res/file/61735879329.pdf
    • http://zonweringbelgie.be/ckfinder/userfiles/files/10954374664.pdf
    • http://aaaexpressac.com/userfiles/file/32876717441.pdf
    • http://akwarella.pl/user_uploads/file/59271515112.pdf
    • http://visualpaint.com/wp-content/plugins/formcraft/file-upload/server/content/files/16096a79615493---tokotodekidiwa.pdf
    • http://xn--80akij1ajew.xn--p1ai/wp-content/plugins/formcraft/file-upload/server/content/files/160856f0771b28---pevigoj.pdf
    • https://vaytieudungtragop.com.vn/wp-content/plugins/super-forms/uploads/php/files/gfhham3pmi2uupsgjso28oupma/24606221440.pdf
    • http://www.gaviprintpack.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f6eeb9c065---71051785666.pdf
    • http://averon.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1606c9face6e60---jokurajasikelirel.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=biblical+meaning+of+estella
    • 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_off0001025e.bin
b7d6383c2a0ba4d8955a087b08fb8450bc1062c42cd9d18cd558dd5d4ccba67f
pdf-font-stream PDF embedded font (sfnt) at offset 0x1025E 19040 bytes
font_01_sfnt_off00013320.bin
011c76d4020a175bf3ee00d7bc320dfc670568c453d32c24006b66063168c42a
pdf-font-stream PDF embedded font (sfnt) at offset 0x13320 10772 bytes
font_02_sfnt_off00014bfb.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x14BFB 16792 bytes