Malicious PDF — malware analysis report

Static analysis result for SHA-256 951bbf5c10296197…

MALICIOUS

PDF

84.1 KB Created: 2021-07-06 00:46:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: ae6cdcdebcc2e396c501d59efcecbc0e SHA-1: 201ef07fdc1d16d171e130ded1c4268846a63738 SHA-256: 951bbf5c10296197c4d23cdbc2d93a3b72657a7d970de9dfa2ed860578fbe90f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple compromised WordPress sites and disposable hosting domains. The embedded URLs, such as 'https://queure.ru/uplcv?utm_term=3+class+english+question+answer', are likely part of a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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://queure.ru/uplcv?utm_term=3+class+english+question+answer
    • https://anukulagrotech.com/ci/userfiles/files/74324322450.pdf
    • https://carthink.org/wp-content/plugins/formcraft/file-upload/server/content/files/160ba279f968dc---77080009657.pdf
    • https://kopari.hu/files/file/58569593021.pdf
    • https://www.scanworld.se/wp-content/plugins/formcraft/file-upload/server/content/files/160bcc7cc087ca---58380800157.pdf
    • http://vksraja.in/fckeditor/upload/file/95939678682.pdf
    • https://aimhc.com/userfiles/file/26785884540.pdf
    • http://remont-elektro.eu/archiv/file/fevomilimibidovog.pdf
    • https://unosms.us/userfiles/file/lokiwapi.pdf
    • https://medok18.ru/wp-content/plugins/super-forms/uploads/php/files/6558606eb52f3db152cdb97a83d2bb0a/35060197998.pdf
    • https://wills.sg/wp-content/plugins/super-forms/uploads/php/files/04c693ebcc603664377908f27372ac83/lilukifevel.pdf
    • https://terravistahometeam.com/wp-content/plugins/super-forms/uploads/php/files/bf6b9c871130200c4402acb0558593c2/85700352892.pdf
    • http://global-gypsum.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086c5dce8da4---982121847.pdf
    • https://bisnismedsos.com/userfiles/file/suzizunilajorelexuvoruwe.pdf
    • http://nuitsdartistes.eu/images/file/30728854592.pdf
    • https://amalighting.com/wp-content/plugins/super-forms/uploads/php/files/2379986dcca1788ceec8221e03c533c8/rizebuxiwinu.pdf
    • http://www.celso.org/download/62765807345.pdf
    • http://bamt.be/wp-content/plugins/formcraft/file-upload/server/content/files/160708c8b5e42b---fepekifulubilejulujezoje.pdf
    • https://www.themeshcowork.com/wp-content/plugins/super-forms/uploads/php/files/dbfad7a3f317c7ff8d0c8b30a167af01/6330148908.pdf
    • http://www.hkqi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b3ecd89ddcd---11506982557.pdf
    • https://adbadog.com/wp-content/plugins/super-forms/uploads/php/files/8eb7ccc27ccc32048b36603069b9c2e1/jibaniwal.pdf
    • https://teplitsyoptom.ru/wp-content/plugins/super-forms/uploads/php/files/a1d6fadfdcac23a3c216463402a31bee/lazilibe.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16093f6bfb5840---29216505039.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_off0000e44a.bin
98561b42b65f5f7de757f00c515f78a5603c2580653c68bad24924e1cb5bf8d5
pdf-font-stream PDF embedded font (sfnt) at offset 0xE44A 10916 bytes
font_01_sfnt_off0000fd4e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFD4E 16792 bytes
font_02_sfnt_off00011560.bin
c17a9ff74064d5bef0ff4b427b5b53bdbbe639567b59d1e8df70f58e747e6216
pdf-font-stream PDF embedded font (sfnt) at offset 0x11560 17704 bytes