Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb6737bd7ca9caf9…

MALICIOUS

PDF

89.5 KB Created: 2021-07-05 19:16:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 3707382abd015c4578be91de6d9f36d7 SHA-1: de5b0d52096a28f9ffa1dc95574b5fd725689c88 SHA-256: cb6737bd7ca9caf90c9959caa3257fb249ae79356150bc2116393d38c8533f53
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Several heuristics point to the file acting as a link farm, directing users to compromised websites and potentially disposable hosting. The embedded URLs, while some are marked benign, are part of a pattern to distribute malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

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.carlosfunes.es/wp-content/plugins/formcraft/file-upload/server/content/files/160ae74bd57787---39193502398.pdf
    • http://www.alwaysflorida.com/wp-content/plugins/formcraft/file-upload/server/content/files/160abaa7feb248---zexevokedar.pdf
    • http://finsura-lifedirect.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160907a0ea55e3---tufedulapix.pdf
    • https://cavalier-hundezucht.ch/userfiles/file/73516072549.pdf
    • https://masterok-kovka.ru/wp-content/plugins/super-forms/uploads/php/files/fd53e588a0f9cb4cd82b0b898d7c3095/mofifipuzanevebakuropeke.pdf
    • https://pfgmm.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160aa3394be617---41925160005.pdf
    • http://www.stratcareerservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c28d72b31d9---xopevusugaje.pdf
    • http://djpress.pl/Image/files/zerakuvi.pdf
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bd8b68b3af6---98989125191.pdf
    • http://dzwigipoznan.pl/userfiles/file/56238875454.pdf
    • http://hytechplus.com/userfiles/file/67960068920.pdf
    • http://www.inhd.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609540732712f---10924915835.pdf
    • https://gz-topstar.com/wp-content/plugins/super-forms/uploads/php/files/54a6eddeadd120f54d3c7210dc063a93/29774814192.pdf
    • http://indecomavo.pl/inc/98749710522.pdf
    • https://miamivanservice.net/wp-content/plugins/formcraft/file-upload/server/content/files/16080b336e09eb---13497422291.pdf
    • http://www.ponderosafestival.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609aeeb018459---19267750256.pdf
    • https://economiadecomunion.net/ckfinder/userfiles/files/wofopaxigujolavobusu.pdf
    • https://aquaticlandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ae00b2cec6---mekezapugegotodeb.pdf
    • http://maasmartcity.com/userfiles/file/98593045332.pdf
    • http://wsp.pl/userfiles/file/kalipi.pdf
    • https://www.acptechnologies.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608e727e35038---31350049856.pdf
    • http://4reality.cz/userfiles/files/makanejasukenux.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=gta+5+online+scary+easter+eggs
    • 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_off0000f918.bin
d1a5f30e0eef4676f86676f4afa3c1d2ae02ce8fc368be7a3025e6685295dbdf
pdf-font-stream PDF embedded font (sfnt) at offset 0xF918 17348 bytes
font_01_sfnt_off00012686.bin
d548e3931d93a6479cc919b5e65197cf08163044629fe78afbc65d2ec998fea0
pdf-font-stream PDF embedded font (sfnt) at offset 0x12686 10692 bytes
font_02_sfnt_off00013f50.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13F50 16792 bytes