Malicious PDF — malware analysis report

Static analysis result for SHA-256 25cdde21cb5c6246…

MALICIOUS

PDF

78.4 KB Created: 2021-09-06 19:49:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 53e90d1747bcdeac861ec27f698d628f SHA-1: 1711c55630d70d64183e323d9892faf92c8c2b1b SHA-256: 25cdde21cb5c6246855440e175a6fbc8d8e23438dbe8a5501801f3066f42bdbb
156 Risk Score

Malware Insights

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

The PDF contains a link farm, with numerous URLs pointing to various domains, many of which are hosted on compromised WordPress sites or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. The presence of multiple external URIs and a link farm suggests an attempt to redirect the user to a malicious payload or phishing page.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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 http://agriturismofattorialucciano.it/ckfinder/userfiles/files/jenavowuwo.pdf In PDF document text
    • http://www.inhd.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160bbcaa11c1e6---tudunipakafifotad.pdfIn PDF document text
    • http://czerwoneiczarne.pl/files/file/kadurafurokote.pdfIn PDF document text
    • https://yz-yongzhong.com/upfiles/editor/files/bowidipipitumapezu.pdfIn PDF document text
    • http://toyotarent.tw/FileData/ckfinder/files/20210731_9826DFB357332E44.pdfIn PDF document text
    • https://alphacleanwashing.com/wp-content/plugins/super-forms/uploads/php/files/5d55a046773abfcfb79a5b0016190a70/88577299565.pdfIn PDF document text
    • https://przygodanaukrainie.pl/admin/ckfinder/userfiles/files/kituzugabo.pdfIn PDF document text
    • https://autoparkalbanese.it/file/89782145866.pdfIn PDF document text
    • https://micast.de/wp-content/plugins/super-forms/uploads/php/files/1955fpu6nhlq1lbjdjl5u9hlj4/52232615458.pdfIn PDF document text
    • http://discarga.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b1289c2e3b9---zonininanav.pdfIn PDF document text
    • http://alibabashipping.com/userfiles/file/3473973522.pdfIn PDF document text
    • https://carstenrath.com/wp-content/plugins/super-forms/uploads/php/files/7umo3av2hres2p44f9ghnnh7qe/ladaxufatenolivotunabered.pdfIn PDF document text
    • https://myphambambi.com/webroot/img/files/muzosorigatamopoxuguge.pdfIn PDF document text
    • http://guowangcable.com/d/files/3674020315.pdfIn PDF document text
    • https://goldgreiner.de/userfiles/file/92356262326.pdfIn PDF document text
    • http://sgpeo.pl/users//file/jemuk.pdfIn PDF document text
    • https://www.focus.mu/wp-content/plugins/super-forms/uploads/php/files/0caa81347efef64327c6ddcdbae44966/deregeke.pdfIn PDF document text
    • http://ozari-ua.com/files/file/81364862816.pdfIn PDF document text
    • http://www.petercar0937494634.com/upload/img/files/busiredajed.pdfIn PDF document text
    • https://sk-developers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f5f4d59bc54---15999191408.pdfIn PDF document text
    • http://mamnonlittlesun.com/upload/files/51402414472.pdfIn PDF document text
    • http://automsystem.com/UploadFile/file/20210604160031025.pdfIn PDF document text
    • http://teknis.it/userfiles/files/33966629983.pdfIn PDF document text
    • http://cana.vn/uploads/userfiles/file/33826314627.pdfIn PDF document text
    • https://webgirls-studio.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c53e919dd87---13846943667.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=los+guardianes+de+las+dimensiones+libro+pdfPDF 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_off0000c9f4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC9F4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e206.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE206 19112 bytes
SHA-256: f2b6c8c8f730a4df654d882b96a5f487dba0cf946fafa268f551c7eea173198a
font_02_sfnt_off0001131c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1131C 10940 bytes
SHA-256: 9e8544a2afb1975e76e9d6e9077eb274e29ec211975d67a2e3c8608e46bc523c