Malicious PDF — malware analysis report

Static analysis result for SHA-256 999a51e853c614dd…

MALICIOUS

PDF

85.1 KB Created: 2021-07-14 08:13:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f22597e36218c5f91a1fcaa8cb560031 SHA-1: c0377b9fc3d5579e364cdcf0cd9ed3ef2e0ac818 SHA-256: 999a51e853c614dd6829b30bdd5c6f185b3669245915b7d1ad261962027c52b2
156 Risk Score

Malware Insights

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

The PDF contains numerous external URIs and links to compromised WordPress upload storage, indicating it functions as a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely to redirect users to phishing sites or download further malware. The presence of multiple distinct hosts and the use of UTM parameters in one URL further support its role as a distribution mechanism.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

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=maths+formulas+for+class+9+and+10+pdf
    • http://izdepskifamily.com/clients/1/1a/1adacdf247316bc4617b3617d965acc7/File/raguradoninewajimafamivu.pdf
    • http://isgsrl.it/images/file/zeveponuvewejizexejelowos.pdf
    • http://adria-ex.com/images/blog//file/kufakakumazeta.pdf
    • https://taksis.lv/taksis/userfiles/file/699911534.pdf
    • http://bonsaichik.ru/images_uploads/files/jijat.pdf
    • http://intechsol.kz/wp-content/plugins/formcraft/file-upload/server/content/files/16072901520be7---30867959483.pdf
    • http://beetsom.com/PROGRAM_FCKeditor_UserFiles/file/8080202306095b1409dafb.pdf
    • https://completecollegestrategies.com/wp-content/plugins/super-forms/uploads/php/files/369b7b9a2226e8a2b6e64327a48be06c/bigiperojozofafim.pdf
    • http://nc2e.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160d8ddb5b7210---43153340585.pdf
    • http://canevinclassof70.com/clients/6/6b/6b8b8ee0d314e59372afbcb75100d768/File/vubotudozeredebexibevugag.pdf
    • https://francoisdaulte.com/ckfinder/userfiles/files/5324338644.pdf
    • http://erbilsunhotel.com/wp-content/plugins/super-forms/uploads/php/files/dbrelpathdekgmtoilqr09eju3/2381190099.pdf
    • http://www.commandinglife.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072a27b8e684---94200431886.pdf
    • http://dzbnf.com/upload/file///5647190968.pdf
    • http://3duct.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ebb8998e85---49180346366.pdf
    • https://na-nule.ru/wp-content/plugins/super-forms/uploads/php/files/gpqavlgeielcfepi1a0292t873/14811838087.pdf
    • https://janeunchained.com/wp-content/plugins/super-forms/uploads/php/files/usqcdk3i9g62ri43ucqmiri1tg/nisowojarepuzaxarasivi.pdf
    • https://pensionatiitalianiinportogallo.it/wp-content/plugins/super-forms/uploads/php/files/6bf9274d4aff1875910679b2f726d2ea/lumepuno.pdf
    • http://iwish-cosmetics.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608e74ac3b665---dexasexopineropebikuroku.pdf
    • https://www.mnspineandsport.com/wp-content/plugins/super-forms/uploads/php/files/9f73f48622eaea0f9253294b1494676e/88908790515.pdf
    • http://drivescuolaguida.it/userfiles/files/54753975058.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_off0000e53a.bin
e75a385b1e7009888ce4b81aeecc6ddcbbf1c88368ad3c569205c11016ebb96a
pdf-font-stream PDF embedded font (sfnt) at offset 0xE53A 11096 bytes
font_01_sfnt_off0000ff01.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFF01 16792 bytes
font_02_sfnt_off00011713.bin
8595d697b22f14a5269b41ff71ac64b79ef9c419ce803ac5c7eb56efc06250fa
pdf-font-stream PDF embedded font (sfnt) at offset 0x11713 18244 bytes