Malicious PDF — malware analysis report

Static analysis result for SHA-256 830c0dfee9e1e306…

MALICIOUS

PDF

81.1 KB Created: 2021-07-21 12:45:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 3b78b3215b4cc1ffd0f44e49728ce9ee SHA-1: 126db579303c607a11d68ca771aa1cf10480dc2c SHA-256: 830c0dfee9e1e306d99d28e8718e144a27fa868a60099995b0de2f7e72ab8ced
156 Risk Score

Malware Insights

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

The PDF file contains numerous links, many of which point to compromised WordPress upload directories, suggesting a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution. No scripts were extracted, but the embedded URLs and heuristic firings are sufficient to assess the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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://intervalhousehamilton.org/ckfinder/userfiles/files/kufabiwaroreburatavavevi.pdf
    • https://dsodrecital.com/wp-content/plugins/formcraft/file-upload/server/content/files/160766bd0e3cdc---48109950181.pdf
    • https://thejasmineway.net/wp-content/plugins/super-forms/uploads/php/files/487tj2b5t3virgtfqpi4qb40re/40245081288.pdf
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/eh4ie45q7oid80l0i71l2cemi1/97035262130.pdf
    • https://www.dentaltaxpros.com/wp-content/plugins/super-forms/uploads/php/files/6ebb4298c756847594cb1a70b38c5695/1929502971.pdf
    • http://vienhung.com/webroot/img/files/rutunaxedadomilusudujiv.pdf
    • http://dent-pro.cz/pic/file/65227115357.pdf
    • https://growlocals.com/wp-content/plugins/super-forms/uploads/php/files/5d8daa205b92857820b798603a4827d1/30575784649.pdf
    • http://smartcookieacademy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606fdcc86c381---verimusiwebamapotofodazuf.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160edc5a67eb2b---31465416167.pdf
    • http://pinetreerealty.ca/clients/55933/File/98974601744.pdf
    • http://poltinik.ru/userfiles/file/pidofanejaxotogub.pdf
    • https://envomask.com/wp-content/plugins/super-forms/uploads/php/files/8b2bff9f6103c6538b09668cdbd96c39/16563753698.pdf
    • https://alignerco.com/wp-content/plugins/super-forms/uploads/php/files/1f30c62499dabdfed66091aa70afe23b/22172032015.pdf
    • https://www.ediliziaindustriale.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c382e6b6ab---vutufozemojezejosutifufol.pdf
    • https://neoville.ru/wp-content/plugins/super-forms/uploads/php/files/922e9d80a1968ffeb6cced51d2893654/renebutasubapi.pdf
    • https://cissud.com/uploads/ck_editor/files/begoto.pdf
    • https://mediabandit.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608019a27bdff---11585995396.pdf
    • https://netwindowvn.com/uploads/userfiles/file/vikubenelavalulijaturi.pdf
    • http://accessprecision.com/userfiles/file/43141081496.pdf
    • http://nuovartea.eu/userfiles/files/wuvifavode.pdf
    • http://xn--rssx31a7tec6p.com/upload/userfiles/files/20210703210508.pdf
    • http://salon-urody-bellis.pl/images/file/77066833145.pdf
    • http://xinyaoqiye.com/upload_fck/file/2021-6-4/20210604084801837075.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=grid+and+graticule
    • 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_off0000d9c7.bin
77692e99262d3908d41ea2370f58930680970127add6586beb2178e3dfa75388
pdf-font-stream PDF embedded font (sfnt) at offset 0xD9C7 10396 bytes
font_01_sfnt_off0000f12b.bin
6c1c03d0b5d1f0de80f24b9570d48d64eb4963a2ddaae4fcdec8108bf3e5d171
pdf-font-stream PDF embedded font (sfnt) at offset 0xF12B 17456 bytes
font_02_sfnt_off00011f81.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11F81 16792 bytes