Malicious PDF — malware analysis report

Static analysis result for SHA-256 c8580551b29c5588…

MALICIOUS

PDF

77.0 KB Created: 2021-09-01 06:51:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 866b7b25560a2a710485b4c4318aedb7 SHA-1: b664e0c8b8632032c12660be0ff2dac1c20af9c1 SHA-256: c8580551b29c558876351a86b1931b8a06c745c1926fc1562ac9e6b0b7351af2
156 Risk Score

Malware Insights

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

The PDF contains a large number of external URIs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9983

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://irlanc.ru/uplcv?utm_term=how+to+remove+column+in+dataframe+r
    • http://conganbacgiang.vn/app/webroot/uploads/files/79066674716.pdf
    • https://scriptdd.com/_file/file/49145347634.pdf
    • https://daynexweb.com/upload/ckfinder/files/67411902381.pdf
    • http://getem.eu/files/file/35715260979.pdf
    • https://namastehealth.in/wp-content/plugins/super-forms/uploads/php/files/p3sqjfuukhhbt4f9dg4uh95a21/66753328985.pdf
    • https://www.helpfulhunks.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16091e2d356cbf---23787926362.pdf
    • http://stillwaterponies83.com/clients/74660/File/lavonibonadovotibutegajit.pdf
    • http://xutricolor.com/uploadfile/files/66116600333.pdf
    • https://rhuyscampingcar.fr/images/files/tagatexibeberepubudegi.pdf
    • https://www.truesdalepainting.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c7724a0673---najajij.pdf
    • http://sweetbasketsbyjackie.com/clients/864293/File/10683719737.pdf
    • http://bright-inter.com/file_media/file_image/file/77007297734.pdf
    • http://www.mvdisposal.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608bfdb84ca99---73585228373.pdf
    • http://botanicgardenscafe.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160a7bbabe91a9---65319383304.pdf
    • http://thaisomboonautopart.com/userfiles/files/18816593148.pdf
    • http://chunmianxian.com/upfolder/e/files/20210821181436.pdf
    • https://fcimoveis.com/imgs/file/penofebilusofix.pdf
    • https://www.spoton.pet/wp-content/plugins/super-forms/uploads/php/files/7srqggneqo458obrs5c2pb8o23/63240896674.pdf
    • http://studiogaleazzo.eu/userfiles/files/99181778300.pdf
    • http://dodici12.ru/wp-content/plugins/super-forms/uploads/php/files/dlkvbnqq0l4hcck1dv52tup5g7/wuxiralox.pdf
    • https://chris-arnold.com/userfiles/file/43054850612.pdf
    • http://candientuvibra.com/images/file/dufikijaruzutigosed.pdf
    • http://livelyway.com/ckfinder/userfiles/files/65519491468.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_off0000c6d3.bin
af3bab8e079da4c0535a51c46e7a951eb92b51b5327c7920fb70e09b9054b0a4
pdf-font-stream PDF embedded font (sfnt) at offset 0xC6D3 17476 bytes
font_01_sfnt_off0000f446.bin
79918b1a1d022244f113f7692ddfb42e21756f012001f3cea95e142fa15a509a
pdf-font-stream PDF embedded font (sfnt) at offset 0xF446 10712 bytes
font_02_sfnt_off00010cdc.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10CDC 16792 bytes