Malicious PDF — malware analysis report

Static analysis result for SHA-256 cd3d85c8cae09189…

MALICIOUS

PDF

82.0 KB Created: 2021-08-10 13:01:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d314cdffa281efb93bb0f018684e9903 SHA-1: 282f7007d885c437352529297899c3116b52288e SHA-256: cd3d85c8cae091892eb42bad689f858c07f0f696fe0290c99267df36f3b5930c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs, many of which point to compromised WordPress upload directories, suggesting a phishing or redirection scheme. The presence of PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics further supports this, indicating the PDF is used to farm links from disposable or compromised hosting. No scripts were extracted, but the primary attack pattern appears to be directing users to malicious external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9986

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://oniceh.ru/uplcv?utm_term=ctet+sanskrit+question+paper+2019+pdf+download
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/160e4d0f22d2da---suzulubamudubeneti.pdf
    • https://butagallery.com/userfiles/files/32486451130.pdf
    • https://cissud.com/uploads/ck_editor/files/nuguvuzib.pdf
    • https://wonwon.taipei/photo/file/48689262126.pdf
    • http://syuncyoku.jp/upload/file/kokudawusajigitipopilire.pdf
    • http://anm-av.de/uploads/files/nakinejadijosabafiva.pdf
    • http://artin-intranet.com/ckupload/files/visamawolezaxipatelet.pdf
    • https://neavocats.com/wp-content/plugins/super-forms/uploads/php/files/39cbd1b500f75023600997d01adb70d0/sixerufolififu.pdf
    • https://allcreaturesinc.com/files/files/jiwobes.pdf
    • http://sxhk365.com/uploads/file///ligajezavibedawiboxufulu.pdf
    • https://www.masismarketing.com/wp-content/plugins/super-forms/uploads/php/files/18c6c75f1ba0d01ff25af090bee4537b/52395750293.pdf
    • https://www.alongsideasia.com/wp-content/plugins/super-forms/uploads/php/files/683dfa93fb45353c78322a2562025fa8/38904002740.pdf
    • http://speakingaboutnetworking.com/ckfinder/userfiles/files/7548038927.pdf
    • https://roweryelectra.pl/app/webroot/uploads/file/16244651298899.pdf
    • https://samarpanbharat.org/trila/userfiles/file/bilolujaram.pdf
    • https://anandamsanyal.com/userfiles/file/zuwaserenevasewa.pdf
    • http://mini-garden.ru/userfiles/file/68743575521.pdf
    • http://unipell.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607d0242305fe---36503289911.pdf
    • http://mirembeestate.co.ug/wp-content/plugins/formcraft/file-upload/server/content/files/160a288c038e5c---78672458700.pdf
    • https://peilimineko.com/userfiles/file/62041332809.pdf
    • https://etcbt.com/userfiles/file/kalufar.pdf
    • https://israelonthehouse.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cda5f042949---dolenebozefavadasapojokoj.pdf
    • http://hoanhaochemical.com/uploads/files/lelowupufilipateragid.pdf
    • https://www.actionconstructionjax.com/wp-content/plugins/super-forms/uploads/php/files/523acf65e9b07f4ed1cde1613f4ef05b/mojepubafa.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_off0000d8d4.bin
5c4a38fd53f70566b762e54bea89b8c0e307450ed4c1ee048a9e13ecd931ea5b
pdf-font-stream PDF embedded font (sfnt) at offset 0xD8D4 16824 bytes
font_01_sfnt_off00010473.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10473 16792 bytes
font_02_sfnt_off00011c8a.bin
6522fe53e9ef031446462761fc682ac76e23e40e0236936ff83cace6b26b7c6e
pdf-font-stream PDF embedded font (sfnt) at offset 0x11C8A 11408 bytes