Malicious PDF — malware analysis report

Static analysis result for SHA-256 910678ff94f7e495…

MALICIOUS

PDF

68.8 KB Created: 2021-09-26 03:16:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 2f51b033cd9ad9b9c5de63f6b83d9631 SHA-1: d1f5a0cb15c27a7f265f256c16f5cad9100ac5fe SHA-256: 910678ff94f7e49577cd67136a8e81fa5e41701e40dbd119cf8d53c58d8fc407
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and link farm behavior are consistent with techniques used to deliver second-stage payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://crysiq.ru/uplcv?utm_term=gangstar+vegas+download+mod
    • https://skinrepublic.vn/webroot/img/files/74681978802.pdf
    • http://alfavit.tv/userfiles/file/54305916511.pdf
    • https://pabausa.org/wp-content/plugins/formcraft/file-upload/server/content/files/161377bc43b968---rigiguvitu.pdf
    • http://saigonford3s.com/uploads/2021-09-04/images/files/23539804814.pdf
    • https://parisautotravel.com/wp-content/plugins/super-forms/uploads/php/files/48kett3i7umpch4a5gfm4fp6r0/winomaku.pdf
    • http://ahjygjg.com/upload_fck/file/2021-9-6/20210906162318867975.pdf
    • https://novamakine.com/upload/ckfinder/files/kuterovodisemure.pdf
    • http://hoangle.vn/uploads/userfiles/file/welaretalizajipezebol.pdf
    • http://phukhoabacninh.com/images/files/diwobapojumulelanimoto.pdf
    • http://hexindechem.com/upload/files/kotutopojol.pdf
    • http://food-cloud.com/home/food-cloud/www/site/site/data/files/refixuridovogarin.pdf
    • https://buildingexpertsdirectory.com/ckfinder/userfiles/files/nuxukegowovurezakagu.pdf
    • https://herfection.herfection.tw/upload/ckfinder_temp/files/20210911163231.pdf
    • http://www.psstrecno.sk/wp-content/plugins/formcraft/file-upload/server/content/files/161389d36de325---88055939456.pdf
    • http://186086.com/upload/files/lipamezemugupokefigega.pdf
    • http://antracit.topmebli.com/content/xuploadimages/file/658664634.pdf
    • https://vaynhanh365.net/contents/files/xadidivavaxalufomi.pdf
    • http://ha-sine.com/d/files/lonokaluzinadelepadil.pdf
    • http://www.accl-calibration.com/login/ckfinder/userfiles/files/dibozedijapodaxo.pdf
    • http://badgerhillfarm.uk/34007025090.pdf
    • https://greenline.bg/userfiles/file/xasikifemumuru.pdf
    • http://airmon.hu/images/files/86205806941.pdf
    • https://dycmc.com/DATA/upload/files/202109112133262077.pdf
    • http://www.contal-farmer.com/uploads/files/94515446576.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_off0000b04b.bin
74d3d8af35fb1d3451cd6ed61812054e402d9c3346e2b535a87172643a99f127
pdf-font-stream PDF embedded font (sfnt) at offset 0xB04B 14780 bytes
font_01_sfnt_off0000d56b.bin
b2c914f2d8432c1d7cb95aca18146392cec0e3f8c27a9f1e65c6f7885e382535
pdf-font-stream PDF embedded font (sfnt) at offset 0xD56B 10692 bytes
font_02_sfnt_off0000eddd.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEDDD 16792 bytes