Malicious PDF — malware analysis report

Static analysis result for SHA-256 8c5a15e21870a7f0…

MALICIOUS

PDF

87.0 KB Created: 2021-08-29 06:11:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: ad8231c93a122a45673763e0130526b1 SHA-1: 740a09a7dbc453b4278da54b8297c410ce207f13 SHA-256: 8c5a15e21870a7f08f23441b50c408663ebeda4d4e523bb0c9980e515d10e256
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs that point to a variety of domains, many of which appear to be compromised or disposable hosting. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of creating link farms on such domains, suggesting a phishing or malware distribution scheme. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or delivering a secondary payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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://crewmak.ru/uplcv?utm_term=most+strikeouts+in+a+season+pitcher PDF link annotation
    • http://sutphinsgermanshepherds.com/clients/21958/File/teziwop.pdfIn PDF document text
    • http://ehs1958.org/clients/73155/File/86522046059.pdfIn PDF document text
    • https://htfcompact.com/wp-content/plugins/super-forms/uploads/php/files/c5b76fd8bb4617927678032cb17b8c7e/zuvipebu.pdfIn PDF document text
    • https://mimpiindah1.com/contents//files/wigelujepuj.pdfIn PDF document text
    • http://mileschapelcme.org/clients/9/9b/9b85db73e8c1d5ae3bc18b6db4f26039/File/69407468664.pdfIn PDF document text
    • http://christopherspubandgrille.com/userfiles/files/31509588427.pdfIn PDF document text
    • http://elsekmont.eu/userfiles/file/fagojefofopawusewo.pdfIn PDF document text
    • https://www.arphplumbing.co.uk/wp-content/plugins/super-forms/uploads/php/files/qblhn8ujvp7cjcvfkppkqb3gao/70132448557.pdfIn PDF document text
    • http://smflow.in/admin/uploads/file/xepalapepuj.pdfIn PDF document text
    • http://abwsalisbury.com/uploads/files/92265149698.pdfIn PDF document text
    • https://limadelimon.com/images/file/12743861101.pdfIn PDF document text
    • http://bbhshipyard.com/userfiles/file/webiverupabalosowut.pdfIn PDF document text
    • http://cahayaapi1.com/contents//files/54731469121.pdfIn PDF document text
    • http://www.victorian-manor.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1606f0e48424da---zisesifefetawudukov.pdfIn PDF document text
    • https://majubesar.net/contents//files/lumagalijumetebidu.pdfIn PDF document text
    • https://velvetskin.pl/wp-content/plugins/super-forms/uploads/php/files/4144e67b526ad129979be0edaada882f/39034699671.pdfIn PDF document text
    • https://aplusadvance.com/naver_editor/data/file/bovomelejunetol.pdfIn PDF document text
    • http://unsersohn.ch/images/file/tesep.pdfIn PDF document text
    • https://www.hsbofmn.com/ckfinder/userfiles/files/kisavefukaxobolijikusipu.pdfIn PDF document text
    • http://www.timtransportes.com/home/wp-content/plugins/formcraft/file-upload/server/content/files/160a80124e5d14---ximupewawotazoxaluwi.pdfIn PDF document text
    • http://www.deadclan.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16102f1aee6e69---50918871006.pdfIn PDF document text
    • https://aedwea.com/upload/foto/fezuwozenolotukixozexak.pdfIn PDF document text
    • http://nickels.design/ckfinder/userfiles/files/dekajedipowe.pdfIn PDF document text
    • http://dangkyidol.com/wp-content/plugins/super-forms/uploads/php/files/bc5utcl5hnb2c74p05pm8urvco/gizefatabepaxosofelup.pdfIn PDF document text
    • 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://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_off0000ee1b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE1B 19772 bytes
SHA-256: 9bb5bf8e6d778ddd7b3ccdde3763e244bdd3e4d265186207974c8bb0c4f532f6
font_01_sfnt_off00012190.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12190 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000139a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x139A7 10612 bytes
SHA-256: aee18118eab89043a49c40d110ce64876cb15484afd2e8ae15e73a0900bf16e0