Malicious PDF — malware analysis report

Static analysis result for SHA-256 cdbb891a5a81a989…

MALICIOUS

PDF

87.4 KB Created: 2021-06-30 10:41:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: ba9ea21271f68db0f9ce735e490ac91d SHA-1: 2b8c26297cd28ff35aea34ff56646668a72cfe0d SHA-256: cdbb891a5a81a98961589d0b948f2ccab0f0777ad63108b9e244de528c1f2311
96 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, suggesting a link farm designed to distribute traffic or potentially host malicious content. The ML classifier strongly indicated maliciousness, and the presence of external links aligns with common phishing or malware distribution tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 5

  • 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://queure.ru/uplcv?utm_term=effects+of+recession+on+families PDF link annotation
    • http://www.contectrade.hu/fckfiles/file/27066867131.pdfIn PDF document text
    • https://www.adelaarenergy.com/wp-content/plugins/super-forms/uploads/php/files/igdaaok81869eb5e9pgsuu6crt/ferutisa.pdfIn PDF document text
    • http://www.mondzorgvesa-voorschoten.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160bf29080bcaa---bukararasedux.pdfIn PDF document text
    • https://sweetestspaparty.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a044f748d28---ramaw.pdfIn PDF document text
    • https://irrisyst.eu/files/file/xatowunebuv.pdfIn PDF document text
    • https://jnfarley.com/wp-content/plugins/super-forms/uploads/php/files/9l0fg97bfju0u48863tlnh3ec2/zosibubidemanefikozo.pdfIn PDF document text
    • http://cs-golfclub.com/ckupload/files/11272799809.pdfIn PDF document text
    • http://mulroyenvironmental.ie/userfiles/file/20770064231.pdfIn PDF document text
    • https://landatur.com/files/galeria/files/69539549656.pdfIn PDF document text
    • http://www.loockuniformes.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/160c4fab086a4f---renetajubawuxove.pdfIn PDF document text
    • https://www.eziblank.com/wp-content/plugins/super-forms/uploads/php/files/5c7060c8cd7fd1cccb19d61fa2e672ff/97043324493.pdfIn PDF document text
    • https://webtraffic.ch/wp-content/plugins/super-forms/uploads/php/files/cpmadusp2iv0r7gt027tqdddpc/88975187087.pdfIn PDF document text
    • http://www.mvdisposal.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bfd6aae4138---lufusalavinefawumuk.pdfIn PDF document text
    • https://motionslam.com/wp-content/plugins/super-forms/uploads/php/files/8de540c3376095cf8366ae4c7d310414/27024207830.pdfIn PDF document text
    • http://erfolgsapp.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606cc27147931---17370570594.pdfIn PDF document text
    • https://abugfreemind.com/userfiles/file/27821794048.pdfIn PDF document text
    • http://diagonal.org.ar/wp-content/plugins/formcraft/file-upload/server/content/files/160b446874f375---bowisuzefefozaged.pdfIn PDF document text
    • http://sochi-polyana.com/ckfinder/userfiles/files/87255202242.pdfIn PDF document text
    • http://www.buildonhope.org/file/wojapujebinexeximibap.pdfIn PDF document text
    • http://thelewisfamilyreunion.com/clients/c/ce/ce72a6ed4f7059d305e3bbfb121cee90/File/zojelolopojerifo.pdfIn PDF document text
    • https://dermo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c36a493f3b7---radutapusomipatutode.pdfIn PDF document text
    • http://benedictinoselrosal.org/ckfinder/userfiles/files/vunajojemukafapewezibi.pdfIn PDF document text
    • 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_off0000f2bb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2BB 10480 bytes
SHA-256: 2fef593557f1e2619c6ebf7c7a675cf958b259692e0721bab492b09584fe9d26
font_01_sfnt_off00010a83.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A83 17584 bytes
SHA-256: b9fd9390c45d52035fcad60fd32c2b6449c5dfbe82b6fdd9e38e6a8b034e80f3
font_02_sfnt_off00013866.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13866 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1