Malicious PDF — malware analysis report

Static analysis result for SHA-256 a36ac38e107d2e93…

MALICIOUS

PDF

77.3 KB Created: 2021-07-08 06:02:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 1febabf3e38db1d0da3c5f768042a629 SHA-1: 4e097f7f6b560e923976987da9fc4c28ff697c54 SHA-256: a36ac38e107d2e930976716e3c96b62addaa74d29fc9dfed59ce5b07cb78a79d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by multiple heuristics as malicious, including a high ML score and ClamAV detection. It contains numerous links, many pointing to compromised WordPress sites and employing link farm techniques, suggesting an attempt to redirect users to malicious content. The presence of these link farms and compromised hosts indicates a likely phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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://www.burit.net/wp-content/plugins/formcraft/file-upload/server/content/files/160acf8b5b4ed6---83634319481.pdf
    • http://www.veronicaneal.com/wp-content/plugins/formcraft/file-upload/server/content/files/1/1606c921cd3701---rawowomolaje.pdf
    • https://mandalaconfeccao.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160de0ff257e54---jixarerofigu.pdf
    • https://kakvkusno26.ru/wp-content/plugins/super-forms/uploads/php/files/6bcb7bb519e94d03dc41f4e68c9901f5/jefuzuxojuviputo.pdf
    • http://gingerbreadvillage.org/clients/e/e3/e396b250b60561adcb946853f9f62e29/File/19127694147.pdf
    • http://federicozucchettiarchitetto.eu/userfiles/files/7216909517.pdf
    • https://www.parkgest.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160858bfcd177c---14009185434.pdf
    • http://krindustria.com.br/site/wp-content/plugins/formcraft/file-upload/server/content/files/160bd4fe9a376c---38929574074.pdf
    • https://cissud.eu/uploads/ck_editor/files/5633924245.pdf
    • http://eastendmediation.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/98418261481.pdf
    • http://strandedtattoo.net/file/fafetufoziledomuzutilodo.pdf
    • http://i-daa-wl.de/userfiles/gowajoparorugememen.pdf
    • http://hani-bee.com/userfiles/files/dafomepozagujoze.pdf
    • https://atamergranit.com/userfiles/file/40104350509.pdf
    • http://altelaw.com/uploads/image/file/70688445043.pdf
    • https://schmitz.cz/res/file/manivozakogugugufeliguru.pdf
    • http://bridgesonthepark.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a70ca632df0---mubejatob.pdf
    • https://hophamthaibinh.com/upload/files/52055473402.pdf
    • https://nailseasupportgroup.com/wp-content/plugins/super-forms/uploads/php/files/6de02492c97e78ddb113025a759be1c7/83614762312.pdf
    • http://druckmaschinenservice.com/uploads/fce/files/20980989458.pdf
    • https://frennphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f65574f14c---36282450985.pdf
    • http://www.playerclub.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16095e12360246---25273437803.pdf
    • http://falls67.com/clients/50406/File/71954342912.pdf
    • https://asigurareingermania.ro/wp-content/plugins/super-forms/uploads/php/files/tt3q9gqhucvh6296d9ald1st0q/81832413160.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=solving+linear+equations+with+brackets+worksheet
    • 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_off0000ca1c.bin
995167f198c66f1eb5f1a9e42cbe4a1eb305816922493da95055d3e52b6266a0
pdf-font-stream PDF embedded font (sfnt) at offset 0xCA1C 16696 bytes
font_01_sfnt_off0000f57e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF57E 16792 bytes
font_02_sfnt_off00010d95.bin
053dfa1f49a45c0ad0f5fd30401c722f415e4afbc29ccf0b0d2f835b9150ce0b
pdf-font-stream PDF embedded font (sfnt) at offset 0x10D95 11212 bytes