Malicious PDF — malware analysis report

Static analysis result for SHA-256 ab9c11dcecd72b17…

MALICIOUS

PDF

80.7 KB Created: 2021-09-20 11:20:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 262bdb202ea5cf6d3d9683f8a5bcc924 SHA-1: fd8b92245a79074cb233329fbece66a38e049faf SHA-256: ab9c11dcecd72b170fa5d253739222961e1940013a75f821b6593183ca0116a6
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised WordPress uploads or disposable hosting, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with malicious document delivery mechanisms.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://cructi.ru/uplcv?utm_term=background+camera+recorder+apk
    • https://cashofferoregon.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138cc61148ee---guniteniwutigixepabuleba.pdf
    • http://hulstcustoms.ru/uploads/files/bomazivutegisemese.pdf
    • https://www.jemelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/16142de18cde85---92355458182.pdf
    • https://hsse.cl/files/33827020435.pdf
    • https://www.lumisolar.pe/wp-content/plugins/formcraft/file-upload/server/content/files/161462e19b76a1---44055571590.pdf
    • http://satyamtracparts.com/userfiles/file/83152854282.pdf
    • http://yenidenyuzlendirme.com/ckfinder/userfiles/files/83804497447.pdf
    • https://lmcmanager.com/ckfinder/userfiles/files/sewewoxetigotuxirunasikun.pdf
    • http://mfo-fond.ru/ckeditor/ckfinder/userfiles/Images/files/pikaxusavelelanizalo.pdf
    • https://rubyyadav.com/nbloom/fckuploads/file/12625629542.pdf
    • http://cp-tournament.org/ckfinder/userfiles/files/bekazugeduwopu.pdf
    • http://aksaxena.com/bpms/includes/fckeditor_uploads/userfiles/file/95231099982.pdf
    • https://seikai.jp/free_images/files/83614293326.pdf
    • http://pegastelco.com/pictures/files/dusesedasulejuzit.pdf
    • http://logtech.cz/foto/Image/file/8773298100.pdf
    • https://samirkumarpaul.com/ckfinder/userfiles/files/wigaxapasebami.pdf
    • http://dogomanhnghia.com/uploads/files/91231533614.pdf
    • https://bednidhitraders.com/userfiles/file/timewixukasinabavo.pdf
    • https://pnlcoach.com/misc2/file/
    • http://ngoinvest.com/uploads/ckfinder/files/nozuwavatanudebagifemof.pdf
    • http://ximangsongthao.com.vn/app/webroot/uploads/files/11054446103.pdf
    • https://rezilta.com/psum/admin/userfiles/file/ragiguvadewuvilofobevawa.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_off0000d414.bin
9b31c2183242c8568bd451a1d387076b6306cdcd7243082fd852ebadcc61fddc
pdf-font-stream PDF embedded font (sfnt) at offset 0xD414 10696 bytes
font_01_sfnt_off0000ec6f.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEC6F 16792 bytes
font_02_sfnt_off00010481.bin
83ad0b4084b630d4e84e7c6a370a0a33b17c0d31a4c1df5ac703d88b0c8088ed
pdf-font-stream PDF embedded font (sfnt) at offset 0x10481 18516 bytes