Malicious PDF — malware analysis report

Static analysis result for SHA-256 a502a971a91ee018…

MALICIOUS

PDF

118.8 KB Created: 2021-07-01 00:29:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e850299782f793202716cb0a5972e386 SHA-1: a20504ed11703254eb94c73f6c8fadeb6b3c0c13 SHA-256: a502a971a91ee0181702faa1b6f348c091425b1b5c77ef26537c4cef9ba6f771
156 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics as malicious, including a high-confidence ML classifier and ClamAV detection. It contains numerous embedded URLs that form a link farm, pointing to compromised websites and disposable hosting, suggesting an attempt to redirect users to malicious content. The file's structure and the presence of external links indicate it is likely used as a lure for phishing or to download further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9958

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://nomylo.ru/uplcv?utm_term=a+membrane+called+the+endocardium+covers+the+heart
    • http://werkkledingverkoop.nl/images/docman/files/21907912112.pdf
    • http://davidhammerstein.org/userfiles/file/pagokupamagujegupote.pdf
    • https://adm.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/bffd855d8c51fb02118a9ee7db87ef5f/vuxupowa.pdf
    • https://www.northernillumination.com/wp-content/plugins/super-forms/uploads/php/files/101ea66a830bb1ab43aae10feb97dfff/sarekuguxa.pdf
    • https://www.taxiserviceh24.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f5d0d4d170---9918196274.pdf
    • https://lakecountyoralsurgery.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f20e422004---46554179695.pdf
    • https://bomberosdenavarra.com/userfiles_nexo/files/xawawolixevekog.pdf
    • http://harasim.cz/uploaded/files/67668315259.pdf
    • http://geoplan.su/userfiles/file/94230983312.pdf
    • https://www.dynasil.com/wp-content/plugins/super-forms/uploads/php/files/c4aa7c04d088a5eaa8ced5eab5fe8ba3/26062601560.pdf
    • http://campbellelectronics.com/uploads/9639370577.pdf
    • https://militarynetwork.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160821917dc377---wonawifeni.pdf
    • http://www.iqubz.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cc6407eb52e---janoj.pdf
    • http://festivaldeliteraturadepereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086274ebb7de---48053875525.pdf
    • https://anthonygillant.com/userfiles/file/jijabeliwomexez.pdf
    • http://aimic.com/userfiles/file/babemisevodabe.pdf
    • http://mgmkt.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a11522002d1---76314488780.pdf
    • https://remoteworkerclub.com/wp-content/plugins/super-forms/uploads/php/files/fa9c58780740d158cb050694986148ca/kuzatosuj.pdf
    • http://www.dnevi-sekretarjev.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160a1dc2e03075---95655340733.pdf
    • https://sevsport.info/wp-content/plugins/super-forms/uploads/php/files/36cbecddb284ea9f53183da28ec5a0b2/12165440842.pdf
    • http://goref.ru/files/file/35178763566.pdf
    • http://lltsg.com/uploadfile/file///2021060318232281.pdf
    • http://cnx.org/contents/6394ffc1-5482-4aa6-923
    • 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_off00016f87.bin
081bef29ff5247c5401de72409d8a47e64d7c93497021027d51e34bc06e5c719
pdf-font-stream PDF embedded font (sfnt) at offset 0x16F87 10920 bytes
font_01_sfnt_off0001889e.bin
8a5f6949d949b72441f8a7c3bcf518d5abc15e26021eaf79ce700424733cab61
pdf-font-stream PDF embedded font (sfnt) at offset 0x1889E 17164 bytes
font_02_sfnt_off0001b581.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1B581 16792 bytes