Malicious PDF — malware analysis report

Static analysis result for SHA-256 1dc7a0604a98bfcd…

MALICIOUS

PDF

69.0 KB Created: 2021-09-27 01:30:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: cbef8088e70a6b23e33206c8492678f8 SHA-1: 733e861ce8f5d355a24a750c7e29c7199c9b364d SHA-256: 1dc7a0604a98bfcd27d0fc4ed4e16b82f303ef5c1995ce84853816d2bef988c1
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It contains numerous embedded URLs, many pointing to compromised CMS uploads or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of external URI heuristics and the overall structure point towards an attempt to exploit users through deceptive links.

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://nomylo.ru/uplcv?utm_term=obb+file+free+download+for+android
    • http://vers-ma.de/userfiles/file/93373505569.pdf
    • http://inlikeflintlogistics.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614f48340e412---vasevatikugoxuxikakuzoku.pdf
    • http://officinedesign.it/userfiles/files/guperavuginiwade.pdf
    • https://anglarill.net/userfiles/file/koxijederowutus.pdf
    • http://sartor.ru/upload/files/48862228867.pdf
    • http://keitbg.com/images/files/tulovubelilalimaligolo.pdf
    • http://www.introspekta.si/ckfinder/ckeditor_uploaded_files/files/71096691638.pdf
    • http://abwingsva.com/uploads/files/worosos.pdf
    • https://pemaboutiquehotel.com/assets/userfiles/files/wazanajidepiwok.pdf
    • http://asztalosweb.hu/userfiles/file/15482523330.pdf
    • http://chickendaylacrescenta.com/uploads/files/jefizefer.pdf
    • http://files.ibiza-ferien.de/file/5401335315.pdf
    • https://velvetskin.pl/wp-content/plugins/super-forms/uploads/php/files/02aaf9f521b02832273925cdbc12cd18/78696778669.pdf
    • http://www.appsolutely.sg/wp-content/plugins/formcraft/file-upload/server/content/files/16141e6e00ec87---wejamawetasozadu.pdf
    • http://glovimex.com/uploads/ckfinder/files/dosizedukunapejaga.pdf
    • http://brickchamber.com/ckfinder/userfiles/files/83877284187.pdf
    • https://tennis94.fr/img/pics/files/22234016716.pdf
    • http://stellarvvv.ru/ckfinder/userfiles/files/17497004691.pdf
    • http://www.1atlanticfunding.com/wp-content/plugins/formcraft/file-upload/server/content/files/16150e31f0e0a6---kedob.pdf
    • https://china-glass-mosaic.vegner.com/userfiles/files/20210918_235943.pdf
    • https://angelsstaff.com/uploads/file/tunoremivagedapit.pdf
    • http://vdi.vn/userfiles/file/rijutunedigejiwi.pdf
    • http://diamant-x.sk/UserFiles/file/1019698269.pdf
    • http://upoart.com/ckfinder/userfiles/files/musofuguzojolerekolofimis.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_off0000b276.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB276 16792 bytes
font_01_sfnt_off0000ca88.bin
03214d50220fce60a48a49c1067b199c2738263da14a72aa0110ed1a5df66985
pdf-font-stream PDF embedded font (sfnt) at offset 0xCA88 14488 bytes
font_02_sfnt_off0000eebd.bin
3fc3da8bf012c92e7820adbd49ff6e8351363dccd46de6b95e2bcfdee20611a2
pdf-font-stream PDF embedded font (sfnt) at offset 0xEEBD 10332 bytes