Malicious PDF — malware analysis report

Static analysis result for SHA-256 d8845d0926711e36…

MALICIOUS

PDF

118.9 KB Created: 2021-07-07 18:11:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 8081989058938e363f6cd3b05a371421 SHA-1: d8cd8fe468fad8d1dff8fa0ab2c02cc00f8531aa SHA-256: d8845d0926711e360ee497ecac7e9ccdfc934b928e225e7c1037dff002f37611
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to compromised WordPress upload directories on various domains, indicating a link farm designed to host malicious content. The ClamAV detection and ML classifier strongly suggest a phishing or trojan payload is intended. The presence of multiple compromised CMS upload links and disposable hosting points to a coordinated effort to distribute malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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 http://stroynerud-sm.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1609badd8f322f---xuvoziwokura.pdf
    • http://uniondeautoescuelas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a6f8268b90---51373342019.pdf
    • http://lichnyiybrand.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607d2a6352f1b---51529822950.pdf
    • http://remontnoedelo.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160a5ed395c4be---90562852090.pdf
    • http://abogadosaguilar.com/ckfinder/userfiles/files/91559572690.pdf
    • https://daismene.it/file/70655936432.pdf
    • http://fletcherfamilyreunion.org/clients/52745/File/60501220401.pdf
    • https://betenagro.com/sites/default/files/file/47964511007.pdf
    • https://vmkstroi.ru/wp-content/plugins/super-forms/uploads/php/files/83869ae3d4b0729760f1f6becdb1ff97/puwatodavasabulawuvudos.pdf
    • https://bnovum.hu/downloads/numad.pdf
    • http://nensi.si/upload/file/61904511912.pdf
    • https://www.grandeprairie.org/wp-content/plugins/formcraft/file-upload/server/content/files/16088ecc8cffb6---5155585961.pdf
    • https://morethancleaningservices.com/wp-content/plugins/super-forms/uploads/php/files/be23e7d43366e57320dd0d500f32e39d/tekotuvavulujexepuwupez.pdf
    • http://training-solutions.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160e0ce63cc508---30074163429.pdf
    • http://geodez.com/pliki/file/94834124582.pdf
    • https://lightsourceindiana.com/wp-content/plugins/super-forms/uploads/php/files/52279e6eb173c6f79f6c5545c6dd6c0d/88085064410.pdf
    • https://landatur.com/files/galeria/files/takujisikabibojagara.pdf
    • http://opalbiosciences.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608bcb7a732ca---77641021539.pdf
    • http://evabody.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16088b8c97a16a---92475417042.pdf
    • http://nicenpos.com/userData/board/file/11622383318.pdf
    • https://lasvegasrebath.com/wp-content/plugins/super-forms/uploads/php/files/3c6f2d3f0edb3a006da9c563977c06d5/veweluv.pdf
    • http://adabaskimerkezi.com/upload/file/82939736085.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=calculating+impedance+in+parallel
    • 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001500c.bin
143227524d617c67c429416c7365dd701977277c08b7ce12c24795349ebebb02
pdf-font-stream PDF embedded font (sfnt) at offset 0x1500C 19944 bytes
font_01_sfnt_off00018586.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x18586 16792 bytes
font_02_sfnt_off00019d9d.bin
7f5fcaf6716ab0162d1dd7796e171a8ba40423d1a3fe447dc758fcec6c199ee9
pdf-font-stream PDF embedded font (sfnt) at offset 0x19D9D 10700 bytes
font_03_sfnt_off0001b5e0.bin
e5f4906ddaa8dd5d5e39e4cbc9407e7c04342156e0e126a74e76b4cfceaecf1f
pdf-font-stream PDF embedded font (sfnt) at offset 0x1B5E0 16360 bytes