Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb03c9f82fa1bb6f…

MALICIOUS

PDF

82.7 KB Created: 2021-08-22 04:13:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 9498e84c68fc6c61a03cbee1d5fdb79f SHA-1: 529d8aca83e0da71e07d8e96bfb53ead543ceb12 SHA-256: cb03c9f82fa1bb6f1a1c5d30322083f5763c6b51de4a35551917c957e9a3e1d0
156 Risk Score

Malware Insights

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

The PDF contains numerous links to external websites, many of which are hosted on compromised WordPress sites or disposable domains, indicating a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware delivery. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://inwebjor.ru/uplcv?utm_term=niveles+de+organizaci%C3%B3n+ecol%C3%B3gica+ppt
    • http://pierrevillers.fr/mairie_files/file/64876577597.pdf
    • https://bor-diing.com/upload/files/99145703033.pdf
    • http://milcontabil.com.br/wp-content/plugins/super-forms/uploads/php/files/34g0bjug15tovtm5od1tqilt56/94343988820.pdf
    • http://cartonwrappingmachine.com/userfiles/file/kimapevile.pdf
    • https://staffxrecruitment.com/wp-content/plugins/super-forms/uploads/php/files/d78ff3c1cc9d1a32d42315bcb60d1b9c/gimisig.pdf
    • http://kcde.kr/userfiles/file/nigakirafenelofepiwabota.pdf
    • https://veritiesinstitute.com/wp-content/plugins/super-forms/uploads/php/files/3f382ed5056ae51e5c036c1e16506f21/xumudalitaxupetule.pdf
    • http://alrabbancapital.com/file/files/fumarakesuxexurexoj.pdf
    • https://soccerauquebec.com/userfiles/file/pejavarin.pdf
    • http://www.ashtralmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d772801a5c4---30309994826.pdf
    • http://brunagabriele.it/userfiles/files/zowoguduxozezedukuvipi.pdf
    • http://abapaposentados.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160e24f9bd58de---89534526794.pdf
    • https://dmddsgn.com/wp-content/plugins/super-forms/uploads/php/files/a13975353a43fd50a17e18a52b1aedf4/nuwanewosajilibiwamirux.pdf
    • http://www.platformliften.info/wp-content/plugins/formcraft/file-upload/server/content/files/1611b546797461---28401592537.pdf
    • http://chixue.com/uploadfile/file/20210522045733.pdf
    • https://www.drserapkagan.com/wp-content/plugins/super-forms/uploads/php/files/quhnuqpc0htl85kltchnad619r/60401075568.pdf
    • http://www.saraviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607abbd3eea0a---xogotowixusib.pdf
    • http://mh-gartengestaltung.de/userfiles/file/53958788393.pdf
    • http://dental-forum.ru/userfiles/file/ritudivutagil.pdf
    • http://bajajsports.com/userfiles/file/newenamukobake.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_off0000d77a.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD77A 16792 bytes
font_01_sfnt_off0000ef8c.bin
5424cf5a572d372bb097511d6258922ffdab0027a9fe8df9960f730ea775c8b9
pdf-font-stream PDF embedded font (sfnt) at offset 0xEF8C 19424 bytes
font_02_sfnt_off0001218d.bin
43b93d0631beaf6dc63f8eb80353bc3ae457c2e4a433a17b5ee2a988990e7e8d
pdf-font-stream PDF embedded font (sfnt) at offset 0x1218D 10928 bytes