Malicious PDF — malware analysis report

Static analysis result for SHA-256 9efecf2b27373ce4…

MALICIOUS

PDF

85.0 KB Created: 2021-09-02 05:42:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 23ea549c255a64f8a2110474a836ea7f SHA-1: 3cecf0c05061223419fc14564462bf5b0a4e43a6 SHA-256: 9efecf2b27373ce4afe3c71ae543fb3e73f94416727e294009ca8f4137daaea7
156 Risk Score

Malware Insights

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

The PDF document contains numerous embedded URLs that point to compromised websites, indicating it functions as a link farm. Heuristics suggest these links are used for SEO manipulation and potentially to distribute phishing content or malware. The ML classifier and ClamAV detection strongly support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://allytemp.ru/uplcv?utm_term=non+dogmatic+meaning
    • https://ksboutlet.com/file/files/77013162593.pdf
    • https://kassa-evotor.ru/wp-content/plugins/super-forms/uploads/php/files/nodekji5snk8e5qmpdh8ib1m7q/6438860728.pdf
    • http://caribsplash.org/wp-content/plugins/formcraft/file-upload/server/content/files/16093f54c2ba25---gifabosokoka.pdf
    • http://ks-system.co.uk/ckfinder/userfiles/files/83084490308.pdf
    • http://bukharageorgia.com/sites/default/files/file/tudizugubezonum.pdf
    • https://singaporenotarypublic.com/wp-content/plugins/super-forms/uploads/php/files/57933e0b29dc22b82dba8367af28ad73/89741540151.pdf
    • http://designklasse.de/ckfinder/userfiles/files/13535970214.pdf
    • https://macauroommate.com/ckfinder/userfiles/files/golav.pdf
    • https://www.actionconstructionjax.com/wp-content/plugins/super-forms/uploads/php/files/3eb14beaa4a8edad0a7649ab7579f3a4/10260529014.pdf
    • http://sddshchb.com/userfiles/file/Fl202107241722544113.pdf
    • https://robert-zauer.cz/userfiles/file/kezadedumobujozeka.pdf
    • http://angelescare.com/userfiles/file/56872568804.pdf
    • https://alfa-pechati.ru/wp-content/plugins/super-forms/uploads/php/files/41af968a5117a16d050aaad4566f1f93/17763518674.pdf
    • https://kfz-gutachter-oliver-schiller.de/wp-content/plugins/formcraft/file-upload/server/content/files/16099441c78c1d---41819485977.pdf
    • http://spl-designs.com/ckfinder/userfiles/files/bagomuxaraji.pdf
    • https://yarsan.ru/wp-content/plugins/super-forms/uploads/php/files/9e4726b620ada14158040cff469ec8e1/54387720555.pdf
    • http://mirembeestate.co.ug/wp-content/plugins/formcraft/file-upload/server/content/files/16092e8458cadf---pafuzevupafofavufodabiro.pdf
    • http://bearings-home.com/userfiles/file/9346869531.pdf
    • https://camgloberealtor.com/userfiles/file/vuxebewazexelupe.pdf
    • https://www.dynasil.com/wp-content/plugins/super-forms/uploads/php/files/a18d51056791a487574057d2e94a3891/bitutimulusemorixibonexaz.pdf
    • http://folientastaturen.pl/_data/file/20604060972.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_off0000e03b.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE03B 16792 bytes
font_01_sfnt_off0000f852.bin
88969c3a71dcbd418cffdb5477ea9f1edb0c774bc5aae91ca8de35ed37c6a237
pdf-font-stream PDF embedded font (sfnt) at offset 0xF852 10376 bytes
font_02_sfnt_off00010f8e.bin
19d680b6e4d48d9056a24dbdc5e2794485fb6a427432fc00a1edd7cdd6396f0c
pdf-font-stream PDF embedded font (sfnt) at offset 0x10F8E 20552 bytes