Malicious PDF — malware analysis report

Static analysis result for SHA-256 4555d98c41d3789b…

MALICIOUS

PDF

76.1 KB Created: 2021-07-09 05:43:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 0bbf4b907ae3ce15ac832992c96815e7 SHA-1: ad8da9fd71145b3c32542988ee131a8807b8fdbb SHA-256: 4555d98c41d3789b9f19653fcd5b4024506ee3ccb63db2ebae582323b19c1937
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised WordPress sites or disposable hosting, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or distributing further malware. No scripts were extracted, and the document body was unreadable, so the attack pattern is inferred from the URL structure and heuristic firings.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://xn----8sbaqfskngn1qi.xn--p1ai/userfiles/file/93323431062.pdf
    • https://pluckywize.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077e59554353---tozujide.pdf
    • https://nicemexico.net/wp-content/plugins/formcraft/file-upload/server/content/files/160a04423ec1aa---mesomepapanizulopikiwazax.pdf
    • https://www.sudburyhighspeedinternet.ca/wp-content/plugins/super-forms/uploads/php/files/c93623a72a9739e500cd43aff2b5f310/56267276417.pdf
    • https://detskeihriska.eu/ckfinder/userfiles/files/kigogoru.pdf
    • http://remontnoedelo.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607d9b2b6a8eb---28694850624.pdf
    • https://asiatravel.kg/wp-content/plugins/super-forms/uploads/php/files/5934ee56162b7766f360e17dc7be0a3f/53986818091.pdf
    • https://atolab.it/wp-content/plugins/super-forms/uploads/php/files/7533854cefc8af5062ca30f81b3fb9cf/kusejodaza.pdf
    • https://www.ideaklinikkadikoy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608468d2daf46---nadojak.pdf
    • https://elicopter-de-inchiriat.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1608446ed510f5---dunumameso.pdf
    • http://ekhoron21.mn/uploads/files/84144602088.pdf
    • https://malimbe.africa/wp-content/plugins/super-forms/uploads/php/files/7f5f7c67a444d261631a040f082d4bc4/lomeluzajox.pdf
    • https://homini.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16084945971508---65628287769.pdf
    • http://www.supercarrentalsofmiami.com/wp-content/plugins/formcraft/file-upload/server/content/files/16091b67329ea7---95101662860.pdf
    • https://aravlicraft.com/cmsCart//upload/file/kobiserilesamepopegireve.pdf
    • https://topjobsnepal.com/ckfinder/userfiles/files/38101049984.pdf
    • https://realestateconnect.biz/wp-content/plugins/super-forms/uploads/php/files/f8p0e7ealui05t4acactp8mll5/tafaravaxazelifutozomovo.pdf
    • https://mangmalungtea.com/userfiles/file/jopawawakituxavunokopasuk.pdf
    • http://sgpeo.pl/users//file/bapezifugomigafoxazu.pdf
    • http://glenbrooksouth1970.com/clients/1/17/17fc1bd13d5538a69f39d58c869d2fc5/File/sogibugani.pdf
    • http://grupogmec.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ca85273c62---92673438114.pdf
    • http://imagespa.mx/wp-content/plugins/formcraft/file-upload/server/content/files/16075f2a93fc94---gixumugufogixogud.pdf
    • https://eslms.com/userfiles/file/84499144747.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=blank+northeast+states+map
    • 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_off0000c6b8.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xC6B8 16792 bytes
font_01_sfnt_off0000deca.bin
1b1b610f68c6e0f09ca790b366985fd82438bc73aee9c1f72fe84e070c2d96c9
pdf-font-stream PDF embedded font (sfnt) at offset 0xDECA 17036 bytes
font_02_sfnt_off00010b5f.bin
50c79d9f68600748158bd0e6e9a16c6213db842a405674dee9cc5248b3af0d51
pdf-font-stream PDF embedded font (sfnt) at offset 0x10B5F 10568 bytes