Malicious PDF — malware analysis report

Static analysis result for SHA-256 99a057474834bb9f…

MALICIOUS

PDF

73.5 KB Created: 2021-09-04 21:10:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 051de8b855b66663b5723faf3396ecaf SHA-1: 91d19e59e555ae0d1db6ff5ff2439e762b264805 SHA-256: 99a057474834bb9fcf7f97a1c8ba0a5eb2679a7a4ffe78fb5db300436c51613e
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised CMS upload directories, suggesting it's designed to lead users to malicious content or phishing sites. The ML classifier and ClamAV detection strongly indicate malicious intent. The file's structure and link farm characteristics align with techniques used to distribute malware or facilitate phishing campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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.siemers-deutschmann.de/wp-content/plugins/super-forms/uploads/php/files/3lc24b7ovg8rht9gb0mvc8i8ql/guzuwoxat.pdf
    • https://ateneoarbonaida.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086bcf41a234---85362704672.pdf
    • https://www.expoagrogto.com/wp-content/plugins/super-forms/uploads/php/files/e2gdsm89a0rk9kmd25bg2au6e3/98601425759.pdf
    • http://gospel-pour-100-voix.com/fichiers/newsletter/file/xofenojebegeruj.pdf
    • http://cuuhoatudong.com/upload/files/zusevisatirifasewofo.pdf
    • https://www.sussexweddingservices.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160728a896a8e9---tijaxovito.pdf
    • https://heritagelogs.com/wp-content/plugins/super-forms/uploads/php/files/uhilndd71rq4gqma3qkpt5fv5m/jakijifopenolu.pdf
    • https://miamiuniquelimo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609629ebcbc5a---gajibaliwizozemipab.pdf
    • http://aescantabria.es/upload/fckeditor/file///1369730276.pdf
    • http://hujiangsy.com/upload/files/41337288614.pdf
    • http://drumlockingclamp.com/FCK_Editor_Images/files/19464241207.pdf
    • https://minutesnap.com/wp-content/plugins/super-forms/uploads/php/files/bad5b34900155522f674a7baa7361f6f/12526619814.pdf
    • https://elitteaccesorios.com/wp-content/plugins/super-forms/uploads/php/files/5p2j3ee1fj1cj8f8n8c3ma1ac8/97541310063.pdf
    • https://sipsib.ru/wp-content/plugins/super-forms/uploads/php/files/1e802dfc35b29bf851c91627a3a805f9/katudilojo.pdf
    • http://vladjurnalist.ru/archive/file/76105092020.pdf
    • https://christianboudreau.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070e7d5b48df---nolusutux.pdf
    • https://canadianrelocation.net/wp-content/plugins/formcraft/file-upload/server/content/files/16087b811f3b3b---suwutalisajuzaluz.pdf
    • https://www.booster-p.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b7f6cda6268---67378986214.pdf
    • https://studiogreenwich.ru/wp-content/plugins/super-forms/uploads/php/files/3aedf2a539050f50f7ee1daeec8d5c26/verokopafetixibuz.pdf
    • http://kurier48.pl/files/userfiles/file/turutipumidexapolibapu.pdf
    • http://argyleliquidations.com/userfiles/files/20395878573.pdf
    • https://hohsingfiber.com/ufiles/files/69161155921.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=interference+of+light+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_off0000c19a.bin
c9fa8ee7b9dd574b7ef75d7751f2de0cda1343f9d710f3db0d3699fce54bc5a5
pdf-font-stream PDF embedded font (sfnt) at offset 0xC19A 10520 bytes
font_01_sfnt_off0000d933.bin
daf0909fc28a5b5e06b984f4c037a8684718a956e739b57858d8d7229dc5c5df
pdf-font-stream PDF embedded font (sfnt) at offset 0xD933 15440 bytes
font_02_sfnt_off00010044.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10044 16792 bytes