Malicious PDF — malware analysis report

Static analysis result for SHA-256 3791406d79d19a3e…

MALICIOUS

PDF

89.8 KB Created: 2021-06-26 21:55:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: e194615fced9689ddbf281a12d582d7a SHA-1: c55dd485d1e11fd848103cb9978f5fbb1c6a082c SHA-256: 3791406d79d19a3e4e005edb97930c48dcd7a2281f7ea979870bed152a70f3d7
156 Risk Score

Malware Insights

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

The file was detected as a malicious PDF by ClamAV and an ML classifier. Heuristics indicate it functions as a link farm, directing users to multiple compromised WordPress upload directories. These links likely serve as landing pages for phishing or to host further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://kayakbranson.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607256b1c2a58---13289266736.pdf In PDF document text
    • https://www.ideaklinik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16081d0a83caaa---xebaxofurufarod.pdfIn PDF document text
    • http://pansophers.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608fd98908a6e---15337280595.pdfIn PDF document text
    • http://www.elsecretodelolivo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608a95a88ceae---20745599454.pdfIn PDF document text
    • http://mellorymotors.ru/admin/ckfinder/userfiles/files/mitedep.pdfIn PDF document text
    • https://orkhaconstruction.com/wp-content/plugins/super-forms/uploads/php/files/6qhadd00uabp4c0cns5n3vseb3/14863094272.pdfIn PDF document text
    • http://www.prieteniitehnicii.ro/documente/file/25428042942.pdfIn PDF document text
    • https://m-co.de/wp-content/plugins/super-forms/uploads/php/files/tlj38ttnluqtrdt5f43oqvunfd/pezuxuladi.pdfIn PDF document text
    • https://htfcompact.com/wp-content/plugins/super-forms/uploads/php/files/478d3861a20633c5b472352e30a64cc9/73345922794.pdfIn PDF document text
    • https://sip7.pl/autoinstalator/sip7.online/wp-content/plugins/super-forms/uploads/php/files/2a4bd160bc2152a1107a7671f20ed70c/125676069.pdfIn PDF document text
    • http://popnmusic.fr/userfiles/file/bolexidobekofo.pdfIn PDF document text
    • http://thedewakohchang.com/image/upload/File/7014791016.pdfIn PDF document text
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160945fe719c2f---kiwiwawun.pdfIn PDF document text
    • https://xn--i1aam8cb.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/c67ed39ced1df68dcf87ad41875599f1/76989933851.pdfIn PDF document text
    • https://www.cfo-search.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bf9941b55e7---38226628488.pdfIn PDF document text
    • http://urparitet.ru/admin/ckfinder/userfiles/files/98429759597.pdfIn PDF document text
    • https://beribuket.ru/wp-content/plugins/super-forms/uploads/php/files/28708f9e7ff3e8024a5132e798ebbfe9/86903523207.pdfIn PDF document text
    • https://harpethvalleypto.org/wp-content/plugins/super-forms/uploads/php/files/156ab58f1edbd71073dcdbe1b0b6165a/27010835284.pdfIn PDF document text
    • http://www.awakohchang.com/image/upload/File/ujuposinudifexe.pdfIn PDF document text
    • http://fitsiluet.cz/data/file/428941330.pdfIn PDF document text
    • http://maternites-catholiques.org/ressource/site-image/files/moxisanedezuda.pdfIn PDF document text
    • http://www.oiseaubleu-promo.fr/userfiles/file/fesuwijulamefumixeguk.pdfIn PDF document text
    • https://action-roofing.com/wp-content/plugins/super-forms/uploads/php/files/b90a7b27562543dcc63a377e96e8f071/gisizogalazivaturonib.pdfIn PDF document text
    • https://x-software.cz/data/file/wekevasexupatozoxerole.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=indiana+jones+you+have+chosen+wiselyPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000fc4f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC4F 17268 bytes
SHA-256: cdc181992ab8e7003f8c72eed1791d8c50884b62d415d6426d7c2669e00905ad
font_01_sfnt_off000128fa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x128FA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00014111.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14111 10716 bytes
SHA-256: 0aeb9ededa3325918875b2c9c23542f30a5235b488517a1d746163de70ffda27