Malicious PDF — malware analysis report

Static analysis result for SHA-256 dc1216a4221c2b41…

MALICIOUS

PDF

88.2 KB Created: 2021-07-16 05:20:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 8ba35d5d3be9f93f3bf775ddb063d251 SHA-1: 29259ffe7013f6b85cf2accb4a4936cf9b5e1542 SHA-256: dc1216a4221c2b412b84ab9b7db9545d25101f4176d7a2e70fe8d3e1105d92d6
156 Risk Score

Malware Insights

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

The PDF file contains a link farm pointing to multiple compromised CMS upload directories, indicating an attempt to host malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. The presence of numerous external URIs and compromised hosting links supports the classification as a malicious document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

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://qualitycountscleaning.com/wp-content/plugins/super-forms/uploads/php/files/36be81f49287c00325d1b20567fe6f05/zogepukazozepalutenuzokux.pdf
    • http://phanphoiongnhuahoasen.vn/upload/files/26934508757.pdf
    • http://www.agrosystem.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160715f44ad7de---surosa.pdf
    • https://actorconseil.com/files/file/kogumop.pdf
    • https://www.cedicar.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ae24b50a13---59897517665.pdf
    • http://omak1968.com/clients/71178/File/18638915236.pdf
    • http://www.sport-konyv.hu/userfiles/file/89001768884.pdf
    • https://szaniterplaza.hu/ckfinder/userfiles/files/juvojotubakubunolusopege.pdf
    • http://megaprestige.ru/uploads/files/96528883595.pdf
    • http://uctodane.cz/UserFiles/File/34086979460.pdf
    • https://dongytueduc.com/wp-content/plugins/super-forms/uploads/php/files/6csr5ka9scoffidbt2vp89g47s/47168271243.pdf
    • http://web68s.com/upload/files/xodupatijasiwomu.pdf
    • http://ngnjl.com/userfiles/files/32169652987.pdf
    • https://popcouncilinstitute.org/wp-content/plugins/super-forms/uploads/php/files/6c4006c1dc43c13bda926094213d8175/7977818886.pdf
    • http://nc2e.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1608aa4a69a177---kotonuxakikesofobilagaba.pdf
    • https://bajrahrs.com/userfiles/file/nemibodifutegirisorotepa.pdf
    • http://xinyuemu.net/assets/202106/files/20210630173328169554.pdf
    • https://nhaban24h.com.vn/wp-content/plugins/super-forms/uploads/php/files/2lp7ce1ccjirf109va97js83dn/bipile.pdf
    • http://bociany.sk/media/file/17608643946.pdf
    • https://www.lightingsolutionsinc.net/wp-content/plugins/super-forms/uploads/php/files/0c420aca8f2ca5af6ed4a883672c3a7e/52827674438.pdf
    • http://dangkykinhdoanhkiengiang.com/upload/ck/files/sezeviropoganukox.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=bass+clef+reading+exercises+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_off0000f4bc.bin
6d526fe6fb198c44848ee629a751b9eb53cc966ae8aa6a52f08a9d10e4f083b0
pdf-font-stream PDF embedded font (sfnt) at offset 0xF4BC 10732 bytes
font_01_sfnt_off00010d4c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10D4C 16792 bytes
font_02_sfnt_off0001255e.bin
ee0870bd440ef7ab92e9ded6d629ebddbe52256addf7a425cf691f2192140bf7
pdf-font-stream PDF embedded font (sfnt) at offset 0x1255E 17600 bytes