Malicious PDF — malware analysis report

Static analysis result for SHA-256 ad77c37d85549ff6…

MALICIOUS

PDF

70.3 KB Created: 2021-09-26 18:53:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 2db4e93cbf9f5d5870243bd5b8aea7fe SHA-1: 9aafa73833dbb93ce7342c292958bbc84abdefba SHA-256: ad77c37d85549ff6536d2bcd20876e4e92a18638bad37e64945f2a34d7954015
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file contains numerous external links, many of which are hosted on disposable domains or compromised CMS uploads, indicating a link farm designed to redirect users to potentially malicious sites. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are indicative of a phishing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://ketchas.ru/uplcv?utm_term=gta+5+apk+obb+1gb
    • http://busangh.com/attfile/fckimg/file///2021092211325_261951740.pdf
    • https://thepetrichortouch.com/wp-content/plugins/super-forms/uploads/php/files/o24kaqdh101legn64jvm55c05c/50052092784.pdf
    • http://autosoftware.company/autoresponders_images/files/daxujuxi.pdf
    • http://snookerfootball.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1614de47c6e56f---wunakiduwin.pdf
    • https://dutchhaves.com/uploads/files/202109201809478575.pdf
    • https://silverlabpupsforsale.com/userfiles/files/fofuwapuzusazoretegu.pdf
    • https://klubkanine.com/home/klub/public_html/ckfinder/userfiles/files/tivogovosabadegod.pdf
    • http://punaide.com/userfiles/files/32962218858.pdf
    • https://emailchopper.rockeit.com/userfiles/file/95066677564.pdf
    • http://aurastaffing.es/upload/file/tizomowiwifevulefukol.pdf
    • https://073741256.com/uploads/files/202109021723278175.pdf
    • http://banlinhkienlaptop.com/userfiles/file/27484792137.pdf
    • https://genia-groupe.fr/images/files/16754965875.pdf
    • http://gulfcoastlist.com/userfiles/file/32600657110.pdf
    • http://pzhjintai.com/upload/files/73650566735.pdf
    • https://advantagelic.com/singhania/downloads/file/2342467506.pdf
    • http://terryloops.com/E/file/28744963075.pdf
    • https://dmddsgn.com/wp-content/plugins/super-forms/uploads/php/files/4dc02007e2f6fa24e88746d980e01c1d/69052799606.pdf
    • https://shiprapublication.com/uniformkontakt/userfiles/image/files/44428307693.pdf
    • https://dichvumayphoto.vn/webroot/img/files/96948545633.pdf
    • http://spellenindex.nl/images/uploads/42881894568.pdf
    • http://abogadosaguilar.com/ckfinder/userfiles/files/76425025867.pdf
    • https://aiwcecckolkata.org/FCKeditor/file/rivesesikidejirumef.pdf
    • http://jysfh.com/upload_fck/file/2021-9-6/20210906171443305619.pdf
    • http://northcity.rs/slike/files/6858155656.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_off0000b3b3.bin
b4e58bd3b2a2a1c47869098f3f4c80e060f20b56b7e51affd592811336587126
pdf-font-stream PDF embedded font (sfnt) at offset 0xB3B3 10244 bytes
font_01_sfnt_off0000cabd.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xCABD 16792 bytes
font_02_sfnt_off0000e2cf.bin
a9fd4d491e6ddcc1ddcf458491f5b85329e360d0a1f6ac3076cad525b76a9d30
pdf-font-stream PDF embedded font (sfnt) at offset 0xE2CF 16052 bytes