Malicious PDF — malware analysis report

Static analysis result for SHA-256 ca271b0331036e00…

MALICIOUS

PDF

84.9 KB Created: 2021-06-25 18:13:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 3ba939522621a7ceeb169d09530ee615 SHA-1: 1f5efb140942311408d13ed37e9d5dd7eac67149 SHA-256: ca271b0331036e0040723f852719f129afa1c422f2ac8d9a1f5233ff53e02cdd
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous links, many pointing to compromised CMS uploads and disposable hosting, indicating a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware delivery. No scripts were extracted, and the document body was unreadable, but the heuristic findings are sufficient to assess the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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://too.kg/wp-content/plugins/super-forms/uploads/php/files/fa1dfd8123ead305940230ceb58c61f5/35267910274.pdf
    • http://xn--80aafkqcanfpgnhbng3b5i9a.xn--p1ai/pict/file/koxukege.pdf
    • https://gresathouse.com/wp-content/plugins/super-forms/uploads/php/files/2051aa43d3acfb17eca22b6c4799833d/pefatozofo.pdf
    • http://careerhack.net/wp-content/plugins/formcraft/file-upload/server/content/files/160774a9a67bdd---56574910942.pdf
    • https://journeypeople.cc/wp-content/plugins/super-forms/uploads/php/files/9d2a61f5b606c79df2e908e88a35f7af/xutavopogov.pdf
    • http://www.belladermeestetica.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16076edb4106f8---zufugujazewenumekotisek.pdf
    • http://www.advokat.com/app/webroot/img/fck/file/73761295339.pdf
    • https://carea2plus.com/wp-content/plugins/super-forms/uploads/php/files/778180ea8f2a9422efc61a258a37335a/16240673075.pdf
    • http://www.orhancoskun.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bc06ccba886---75257501068.pdf
    • https://www.temsilcifirsatlari.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607db0377d786---63144361156.pdf
    • http://www.ambredore.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a725e4c16a4---48320196913.pdf
    • http://opuspoint.com/ckfinder/userfiles/files/70675414693.pdf
    • http://cestovni-postylka.eu/userfiles/file/30777623100.pdf
    • https://alakharia.com/public_html/userfiles/file/91558306186.pdf
    • http://www.eflox.net/wp-content/plugins/formcraft/file-upload/server/content/files/1606d0a9f425dc---livuveniximokimeviv.pdf
    • http://drvision.org/wp-content/plugins/formcraft/file-upload/server/content/files/160ae76b918da9---votedasaforumosak.pdf
    • https://sammycar.ch/sammy/sites/default/sammyfiles/newsletterfile/62249883715.pdf
    • http://bezpiecznamlodosc.org/files/file/rejipaxiniruxoxamuf.pdf
    • https://alice-immo.com/userfiles/file/saviwiririnuk.pdf
    • https://118highschool.am/wp-content/plugins/super-forms/uploads/php/files/ed85c4441d88c8eabc97d5cdc882aff2/dolivixotazotujemeteseleb.pdf
    • https://thealloywheelcentre.co.uk/wp-content/plugins/super-forms/uploads/php/files/e9629964dd1a659b4eba7c56f177f567/nabuvogosiluzafepag.pdf
    • https://pilotcenter.gr/wp-content/plugins/super-forms/uploads/php/files/689rh3jh93jb2fo4jsp8demauq/88221212435.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=emotional+guidance+scale+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_off0000e8dd.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE8DD 16792 bytes
font_01_sfnt_off000100ef.bin
c6f539b36646d76146633012d2cae861b9e211734ce2d496d04d8c28d729cb08
pdf-font-stream PDF embedded font (sfnt) at offset 0x100EF 17032 bytes
font_02_sfnt_off00012d28.bin
a01d75c42d94e1a79560ca8040068f6ca66453e97db4a2bf090d8b9b5d3b162b
pdf-font-stream PDF embedded font (sfnt) at offset 0x12D28 10948 bytes