Malicious PDF — malware analysis report

Static analysis result for SHA-256 b63bd28ce106b9d7…

MALICIOUS

PDF

69.8 KB Created: 2021-09-26 21:53:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: bf8316b9900a49bb689359ba5759c696 SHA-1: 92dd6458ceaf3f6ed2d7e586ec7a294ce197bedb SHA-256: b63bd28ce106b9d7301f7e0a7b49b019a3db79dd847583a53c538d53d90e529b
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to compromised WordPress upload directories or disposable hosting, suggesting a link farm designed to redirect users. The heuristic 'SE_PASSWORD_ARCHIVE_LURE' indicates the document likely instructs users to open a password-protected archive, a common tactic to bypass gateway scanning. ClamAV detection and ML classification confirm its malicious nature, likely as a phishing or downloader document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Password-protected archive handoff high SE_PASSWORD_ARCHIVE_LURE
    Document gives password instructions for an archive or attachment — often used to keep payloads encrypted until after gateway scanning
  • 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=delete+duplicate+contacts+android+phone
    • http://sbsedupatti.com/sbsedupatti/userfiles/file/tuwonira.pdf
    • http://lepal.sk/ckfinder/userfiles/files/kabezofisiwadofulezipuz.pdf
    • https://drakbera.com/ckeditor/ckfinder/userfiles/files/xapetazifamisi.pdf
    • http://noavarservice.com/ckfinder/userfiles/files/jamonurivufosadavune.pdf
    • https://primeodontorj.com/wp-content/plugins/super-forms/uploads/php/files/a6e2556c7add6a622333b4b370804567/97074812311.pdf
    • https://cleartunemonitors.com/ckfinder/userfiles/files/lipisuxiri.pdf
    • https://hoatuoi360.vn/uploads/files/dogizusojizozumukonu.pdf
    • http://yevres.fr/ckfinder/userfiles/files/lanikewiloxaziwag.pdf
    • http://jamalcar.com/userfiles/file/wafebebapuzakajopaj.pdf
    • https://toananhmedical.com/uploads/files/2735269467.pdf
    • https://xnkvinatimex.com/uploads/files/99485105001.pdf
    • https://callmarkinvestments.com/callmark/files/dibek.pdf
    • http://kingkady.cn/uploadfile/files/18942056443.pdf
    • http://aliguoriarchitetto.eu/userfiles/files/60857271362.pdf
    • https://www.dogandemir.av.tr/paketler/ckfinder/dosyalar/files/59818884025.pdf
    • https://energiadirect.pl/application/resources/ckfinder/userfiles/files/nanatovuvefosixexara.pdf
    • http://dmn.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1614d842c1e94c---katetarus.pdf
    • http://hydrem.ru/images/file/gujoxexamezovidomojobomiz.pdf
    • http://wignaccent.com/FCKeditor_2.6.3/userimages/file/20210922191718.pdf
    • http://uro-medical.pl/zdjecia/fotki/file/33232633473.pdf
    • http://ippon.lv/uploads/File/nasiba.pdf
    • https://hotelristorantenovecento.it/wp-content/plugins/super-forms/uploads/php/files/7e39071ab82eaf1dd4a7e1c765fa270a/mofulanojajudobisazuv.pdf
    • https://detectagsafety.com/ckfinder/userfiles/files/88639484256.pdf
    • http://www.ecvbrass.ch/user/web/file/jejiraburebotivep.pdf
    • http://studiolaviano.it/userfiles/files/66940874510.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_off0000b3fb.bin
17d8a9ecc1575555f360464a2e76f271a8450c651a4f26b12db7a38fc7463bbb
pdf-font-stream PDF embedded font (sfnt) at offset 0xB3FB 10712 bytes
font_01_sfnt_off0000cc7e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xCC7E 16792 bytes
font_02_sfnt_off0000e490.bin
c3d4169a45126f7485e667f0bf069ad175e94f65f2355fe7cfd3c46bd53c0a6e
pdf-font-stream PDF embedded font (sfnt) at offset 0xE490 14656 bytes