Malicious PDF — malware analysis report

Static analysis result for SHA-256 a7d395169c36b387…

MALICIOUS

PDF

87.0 KB Created: 2021-06-29 20:07:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: cc09dfff80fda22770157e8d9a06adc1 SHA-1: 12096d0116c41d52a04b83325d261aa03b0a2d0d SHA-256: a7d395169c36b38713c67ca2cb9c63c5f64cd9efcf0f13596cd3c10e3bb3ebb2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous embedded URLs pointing to compromised WordPress upload directories and other disposable hosting. The primary attack pattern appears to be directing users to potentially malicious content or phishing sites, leveraging compromised infrastructure for distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://coretry.ru/uplcv?utm_term=how+can+you+make+brown
    • http://kolasinprevoz.rs/slike/files/boxuxojoxiguwikapuxaruf.pdf
    • http://salonorganica.ru/upload/files/xezekubebuxelewu.pdf
    • http://queuemanagementsystems.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079d8fff3a1a---futaxi.pdf
    • http://krindustria.com.br/site/wp-content/plugins/formcraft/file-upload/server/content/files/160b64d3c03920---47681507071.pdf
    • http://gennarimaq.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609f942fb100f---59897939369.pdf
    • https://iamluno.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d22cb000be---11128677651.pdf
    • https://wfca-czech.cz/temp/userfiles/files/kiparusavavejotitajisut.pdf
    • http://raduzhniy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b33c31249d7---45073397230.pdf
    • https://dfa-finanz.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606f253a30fb0---42127144244.pdf
    • http://erfolgsapp.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606d126e18e19---14862945157.pdf
    • http://hoangnamjsc.com/upload/files/lunojerobevasizerofusoku.pdf
    • https://anmimar.com/royal/userfiles/file/sulowidomobin.pdf
    • https://ratco-hardware.com/Ups/files/rolifurowepofetizobububa.pdf
    • https://rhdplumbing.com/wp-content/plugins/super-forms/uploads/php/files/a0476daecb74d6fe5cf3fe7326003599/81681795148.pdf
    • https://www.cedicar.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608989bb3f367---zixetewiwa.pdf
    • https://nikosdimos.gr/userfiles/file/repazowutilenurixazoguzis.pdf
    • http://www.iycadana.org/wp-content/plugins/super-forms/uploads/php/files/ifaukamk5e4b9rhm6iib52k3e0/gijotovivas.pdf
    • https://www.helpforbusymums.com/wp-content/plugins/super-forms/uploads/php/files/aae8decb550879c5437dd8e117918947/katadexedafeze.pdf
    • http://lovewhereyoulv.wpengine.com/wp-content/plugins/super-forms/uploads/php/files/705ba472b73ba1a0708c109db8d96f15/37068482602.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_off0000f482.bin
370073f6b41d9cf55484b6387177e0780a14a0b6463d5b32663c1cac917fe740
pdf-font-stream PDF embedded font (sfnt) at offset 0xF482 16772 bytes
font_01_sfnt_off00011fa7.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11FA7 16792 bytes
font_02_sfnt_off000137be.bin
eee877c07dc37fb55f88d79177dd901a47a9d71043c75a4b543936e360e0cf1d
pdf-font-stream PDF embedded font (sfnt) at offset 0x137BE 10508 bytes