Malicious PDF — malware analysis report

Static analysis result for SHA-256 37b16289e2247e60…

MALICIOUS

PDF

81.2 KB Created: 2021-09-18 12:46:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 34d5c8bd6ec7950c05e05d734418bc16 SHA-1: 72cc7b7096e74f6abd4372599dbd949dc3493b06 SHA-256: 37b16289e2247e601e733bb5375bd254991233a283a414922f54ec1940bc2049
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to potentially compromised WordPress sites or disposable hosting, indicating a link farm for SEO poisoning or phishing. ClamAV detected this as Pdf.Phishing.Trojan, and ML classifiers also flagged it as malicious. The document body is unreadable, but the heuristics strongly suggest a malicious intent to redirect users to external, potentially harmful, URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://radekslodkiewicz.pl/files/file/gojodatowufifonugapa.pdf In PDF document text
    • http://ipjanah.ir/wp-content/plugins/super-forms/uploads/php/files/s73b07v83uknf41kj4mhgq9jhu/gilenuz.pdfIn PDF document text
    • http://kiapelhrimov.cz/UserFiles/File/pivuluvabupis.pdfIn PDF document text
    • http://status.cz/UserFiles/File/widisiketanuwem.pdfIn PDF document text
    • http://rem-proekt.com/f/file/rowegijusupolijur.pdfIn PDF document text
    • http://tdjl.com/uploadfile/file///2021091614281155.pdfIn PDF document text
    • http://lemma-studio.pl/userfiles/file/kobakegelilimopubimam.pdfIn PDF document text
    • http://technology-mp.it/userfiles/files/33963802177.pdfIn PDF document text
    • http://www.thelawchamber.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b63f9c67f2---guzozedewakenogimabage.pdfIn PDF document text
    • http://www.adanakursmerkezi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136c9cf82c90---gipawepo.pdfIn PDF document text
    • http://smlstripedbass.com/home/rock/public_html/ckfinder/userfiles/files/42519455901.pdfIn PDF document text
    • https://norservis.info/files/files/76000714969.pdfIn PDF document text
    • https://eetravel.net/file/dujibujazetob.pdfIn PDF document text
    • http://okmarin.ru/userfiles/file/30002826073.pdfIn PDF document text
    • https://klubkanine.com/home/klub/public_html/ckfinder/userfiles/files/tuzimelevisawisopipin.pdfIn PDF document text
    • https://kluchar.net/klucharnet/images/file/79420946089.pdfIn PDF document text
    • https://inprovitchile.com/ckfinder/userfiles/files/vipulewosasofezin.pdfIn PDF document text
    • http://cdseoulps.com/uploadfile/fckeditor/file/75436607097.pdfIn PDF document text
    • http://www.zav-mito.si/wp-content/plugins/formcraft/file-upload/server/content/files/1613a14d62637a---79809521340.pdfIn PDF document text
    • http://techmechengineers.com/uploads/zerovelozagopoj.pdfIn PDF document text
    • https://tpk-m.ru/files/file/zevirikeponaxapekuzoz.pdfIn PDF document text
    • http://velkoobchod-man.eu/ckfinder/userfiles/files/poronevoxazizem.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=video+editor+for+windows+7+64+bitPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d86f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD86F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f086.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF086 10628 bytes
SHA-256: d396c5394727ee250097393b34dd936c796cc37685572005d672385aab33ffcf
font_02_sfnt_off0001091d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1091D 17980 bytes
SHA-256: b1997b891560247301137016e4365329d5df4a5c2f0750ba17b53e7a8dd1e825