Malicious PDF — malware analysis report

Static analysis result for SHA-256 c5986abf4844a790…

MALICIOUS

PDF

73.2 KB Created: 2021-09-25 17:05:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: cdf049f3536af80fccb54cafd44c2f45 SHA-1: a919415261780d90fe3759d12a7c09775daf2caf SHA-256: c5986abf4844a79072d8a297b192e8a7d98fb1d4c3a5e1b6f50590930a906c03
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous external links, many pointing to compromised CMS upload directories or disposable hosting, suggesting a link farm or phishing lure. The presence of PDF_URI and PDF_SEO_DISPOSABLE_LINK_FARM heuristics further supports this, indicating the PDF's primary function is to redirect users to potentially harmful external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://pistant.ru/uplcv?utm_term=warrior+cats+dawn+pdf
    • http://puzynowska-kancelaria.com/userfiles/file/82519335962.pdf
    • http://xn--b1agjlwjc3g.xn--p1ai/ckfinder/userfiles/files/jidubavikarej.pdf
    • http://saludocupacionalpso.com/home/wp-content/plugins/formcraft/file-upload/server/content/files/161318becdb571---62387316763.pdf
    • http://2015.letnifestiwal.pl/ckfinder/userfiles/files/pivoxujitemera.pdf
    • https://digicpictures.com/downloads/tofudewulafarivi.pdf
    • https://www.bluegreenshouseboats.in/wp-content/plugins/formcraft/file-upload/server/content/files/1613af83ce5bcd---91952484554.pdf
    • https://kuechentreff-schmid.de/wp-content/plugins/super-forms/uploads/php/files/h7he54evu8h3n15cvr2q7o84p3/kirotadevagavelowoz.pdf
    • https://worldmedglobal.com/userfiles/files/10371272932.pdf
    • http://immobilieninvestors.eu/userfiles/file/rozokowupugefepigubipi.pdf
    • http://kammed.com/userfiles/file/revowegovokiri.pdf
    • https://soenen-pneus.com/upload/file/27600911929.pdf
    • http://uptindia.com/newsimages/file///82661606508.pdf
    • http://rheumatology.institute/upload/content/file/68545533187.pdf
    • https://sdyh.gr/wp-content/plugins/super-forms/uploads/php/files/1uvsbs7tcvvoij3knjkvt5ld92/fededigaki.pdf
    • https://careerroots.net/ckfinder/userfiles/files/79539866237.pdf
    • https://marljivo.hr/userfiles/file/degivaxawujimesovupom.pdf
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131048934a5f---1851513854.pdf
    • http://ahcxdq.com/uploads/file/081626295229.pdf
    • http://steclotildehorton.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16139ab0fd103a---puremelemi.pdf
    • http://www.sushmitamukherjee.com/fckimages/file/61356705877.pdf
    • https://fmpride.com/wp-content/plugins/super-forms/uploads/php/files/b5b7f6fe49395bb766fb9957cdea28a1/80530159132.pdf
    • http://houstontca.org/Content/uploads/files/98004404735.pdf
    • https://dom4m.de/userfiles/files/82765808377.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_off0000b549.bin
49ca8af84931b3dda1d8395f4917448094b8d97d77de701d68e7f796b1899dc4
pdf-font-stream PDF embedded font (sfnt) at offset 0xB549 10512 bytes
font_01_sfnt_off0000cd68.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xCD68 16792 bytes
font_02_sfnt_off0000e57a.bin
d86e34cb5517333d0512d805c08106b0cfb10e752c8188f0f8ec265dcde75516
pdf-font-stream PDF embedded font (sfnt) at offset 0xE57A 19212 bytes