Malicious PDF — malware analysis report

Static analysis result for SHA-256 b06c8587abe8e5af…

MALICIOUS

PDF

74.0 KB Created: 2021-09-02 06:12:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 99aa8792e5bcb7a61c3810e520770503 SHA-1: f0d0e2b13a54e2183f930e753bdbc7077f5dcad1 SHA-256: b06c8587abe8e5afab09507b0d8820c409b8fb776036106295d7796ccf930ee0
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection and an ML classifier indicating a high probability of maliciousness. It contains numerous links, many pointing to compromised CMS uploads or disposable hosting, suggesting a link farm designed to redirect users. While no scripts were explicitly extracted, the presence of external URIs and the overall structure indicate an attempt to lead the user to malicious content, likely as part of a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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 http://valdhans.cz/userfiles/file/bigefizupu.pdf
    • http://digivideos.net/ckfinder/userfiles/files/2036342319.pdf
    • http://mijinmotor.com/fckeditor/userfiles/file/2473532669.pdf
    • http://adance0112.com/upfile/editor/file/6342169505.pdf
    • https://regiefranchet.fr/userfiles/files/83949616131.pdf
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/16088611862694---71091682704.pdf
    • https://webhostmurah.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608e160cbf9a3---nedopib.pdf
    • https://fiambreszav.com/wp-content/plugins/super-forms/uploads/php/files/a54ad7a612d348d24fea73166ed6c2eb/42249030678.pdf
    • http://mentaplywood.com/images_upload/files/seroz.pdf
    • http://szjwwj.com/userfiles/file///68127644999.pdf
    • http://kppzp.pl/userfiles/file/sewedi.pdf
    • https://shining4u.com/wp-content/plugins/super-forms/uploads/php/files/c4bd0d3065e852101e99d5c94b059ebc/87637239763.pdf
    • https://floridainvestment.cz/files/file/vivunisiwoguvavivimadu.pdf
    • http://mama-care.com/UserFiles/file/vilowirakowete.pdf
    • http://sbs-group.co/userfiles/files/wikonarax.pdf
    • http://abapaposentados.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b307f6ab1be---wevezilu.pdf
    • http://kangs78.com/clients/66216/File/78911249467.pdf
    • https://sipsib.ru/wp-content/plugins/super-forms/uploads/php/files/da094078e7449cf870186650f57d6be0/wenutonu.pdf
    • http://saigondome.com/uploads/userfiles/file/fofefuguderijutetakot.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=pgt+pro+graphics+toolkit+with+advance+settings
    • 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_off0000bd32.bin
f758340268e2c041094f86a253d596ea9d9ba5cb36487405e171d5d63c0e218b
pdf-font-stream PDF embedded font (sfnt) at offset 0xBD32 16292 bytes
font_01_sfnt_off0000e6db.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE6DB 16792 bytes
font_02_sfnt_off0000fef2.bin
19e317bddf70d0b178a8d15618d0bf60099b078684f140322e8c8061badea42e
pdf-font-stream PDF embedded font (sfnt) at offset 0xFEF2 11040 bytes