Malicious PDF — malware analysis report

Static analysis result for SHA-256 a7509afe1ce6fced…

MALICIOUS

PDF

79.0 KB Created: 2021-09-21 13:32:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: ed9d7987f0fa82dc8fa674a0643aac6a SHA-1: eb1a19f84bd786e1a0d2476dcc8ed32c7a3493eb SHA-256: a7509afe1ce6fced759f8ff5718e871c9df7fa706cb1fb50939cf013af5a9faf
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many of which are hosted on compromised CMS platforms or disposable domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9958

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://medvor.ru/uplcv?utm_term=spam+messages+on+android+phone
    • https://weboonline.com/ckfinder/userfiles/files/69219395970.pdf
    • https://tavfelugyelet.megujuloenergiapark.hu/admin/ckfinder/userfiles/files/41954704414.pdf
    • http://dobraukraina.org/sites/all/sites/dobraukraina.org/files/giwikavo.pdf
    • http://frederickfollows.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1613c9b4613038---89866143079.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16147ea78d9c1a---34014341895.pdf
    • https://coonvalleycc.com/userfiles/file/3757996536.pdf
    • http://yatros.ro/wp-content/plugins/formcraft/file-upload/server/content/files/161453a1a4ee3f---51524354333.pdf
    • https://transcendenceit.com/wp-content/plugins/super-forms/uploads/php/files/f899f5d7485f6a2255149e8b81ea82c6/bekukimaguwumofobeserives.pdf
    • http://antitumor.org/filespath/files/20210912025519.pdf
    • https://taptigrihnirman.com/singhania/downloads/file/refajale.pdf
    • http://asqcert.net/files/files/4083166404.pdf
    • http://naphogacomposite.com/upload/files/winevolegusejalubokuz.pdf
    • https://jfava.gemwareserp.com/userfiles/file/8068309641.pdf
    • http://mineraux-et-lithotherapie.fr/ckeditor/upload/files/68390741247.pdf
    • http://scard.vn/app/webroot/uploads/files/36290223597.pdf
    • http://mondoacquapiscine.com/userfiles/files/kijajepomumobimis.pdf
    • https://noursportevents.com/wheelmarine/userfiles/file/88916106019.pdf
    • http://maksimetall.ru/files/rusujuf.pdf
    • http://lenosada.sk/editor_uploads/files/paratolefagu.pdf
    • http://seanmore.com/userData/board/file/38981679140.pdf
    • http://www.39koratmachinery.com/file_upload/files/newapu.pdf
    • http://belv.ru/userfiles/file/1120393002.pdf
    • http://balalajka.nu/media/sutiwadubexavalokogalo.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_off0000d474.bin
23b4308b5b1abfe9b3bee5e4bb29144c44099867cdc83a68cb9fa3a5ac983842
pdf-font-stream PDF embedded font (sfnt) at offset 0xD474 16240 bytes
font_01_sfnt_off0000fe64.bin
f70f96cc62beacf1c9f65e53853d96b2edcb6f6531e4e032fbd0f28054ffbd1f
pdf-font-stream PDF embedded font (sfnt) at offset 0xFE64 10768 bytes
font_02_sfnt_off000116ad.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x116AD 16792 bytes