Malicious PDF — malware analysis report

Static analysis result for SHA-256 a6b3f3aae82b2ad5…

MALICIOUS

PDF

80.9 KB Created: 2021-06-27 22:11:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 986e60da1ef624a6aa62010c4bb778aa SHA-1: 44c5fe75e2b9def9c7716d4ca8e5f030abb3a19e SHA-256: a6b3f3aae82b2ad549d28e6250aaa74ebdecd61a84e9cd1c0ec89b5d05c45cad
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous embedded URLs pointing to compromised WordPress sites and other domains. These links likely lead to phishing pages or serve as downloaders for further malicious payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9950

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://noks.cz/wp-content/plugins/formcraft/file-upload/server/content/files/1608c8015c5b42---37186962387.pdf
    • https://www.gasserbush.com/wp-content/plugins/super-forms/uploads/php/files/ccab5dcd1dbcf36ae54ae09bac814c0b/36554203319.pdf
    • https://himalayanthailand.com/image/upload/File/petuvaginirid.pdf
    • http://www.louthadventures.ie/wp-content/plugins/formcraft/file-upload/server/content/files/160a47ca55490e---54602539421.pdf
    • https://halobysciton.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b5f41e6de87---zosuve.pdf
    • http://conwaychristian.org/wp-content/plugins/formcraft/file-upload/server/content/files/1608d25982bcad---nesuzilaketejepa.pdf
    • https://hoovermaids.com/wp-content/plugins/super-forms/uploads/php/files/418ed5d5b77d936e19e7df2157f90c9d/nifesamabaxoduxupajo.pdf
    • http://zdravi-kromeriz.cz/files/file/44991061383.pdf
    • http://sochistandart.com/ckfinder/userfiles/files/78004513447.pdf
    • https://boumqueur-edition.com/upload/fckeditor/file/gasexij.pdf
    • http://xn--80aaeiengkwpz6p.xn--p1ai/pub/file/14972738884.pdf
    • https://www.karenlovelee.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bbfc9938ac1---13583608540.pdf
    • http://bestforfishing.com/wp-content/plugins/super-forms/uploads/php/files/e517c6dad6432ddea453db34ab929d50/54301564683.pdf
    • https://www.andimoda.com/wp-content/plugins/super-forms/uploads/php/files/eb28431a63f9d9d6d0645c76023b933c/sezaz.pdf
    • http://allnatureint.com/userfiles/file/zowemowapoxiritegil.pdf
    • http://teplospectr.ru/images/files/xugonopelopawuxalesig.pdf
    • https://srp-galabau-rostock.de/wp-content/plugins/super-forms/uploads/php/files/nghkto7kft2tu2i5ujsctr6ca6/74044395134.pdf
    • http://namthangbasaltstone.com/uploads/image/files/tudij.pdf
    • https://educhina.mn/editor/files/tigexujimuluvojere.pdf
    • http://sun-green.nl/ckfinder/userfiles/files/kodotedesoj.pdf
    • http://europeanprofservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160744438ce7c4---83406320868.pdf
    • http://www.x454.com/wp-content/plugins/super-forms/uploads/php/files/u518o50jc5oa6imdjr453uut31/43053084440.pdf
    • http://www.guaitoli.eng.br/wp-content/plugins/formcraft/file-upload/server/content/files/160780f2611a67---ganupejebegirolekiz.pdf
    • https://vegas-shop.net/uploads/files/fewakoga.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=pdf+converter+in+excel+free+download
    • 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_off0000d856.bin
917406866338b81f4ecc66dae0d05ccbe0252ce7471b896d1cd620de22ac0e13
pdf-font-stream PDF embedded font (sfnt) at offset 0xD856 16728 bytes
font_01_sfnt_off00010414.bin
0e73056af108fba79cc4c04e59d87be6e67748bcc76f10ce4c9373e15decf91b
pdf-font-stream PDF embedded font (sfnt) at offset 0x10414 10556 bytes
font_02_sfnt_off00011c5b.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11C5B 16792 bytes