Malicious PDF — malware analysis report

Static analysis result for SHA-256 85878a9e14a45984…

MALICIOUS

PDF

85.2 KB Created: 2021-08-20 08:31:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: d3b576e83d61aede65c50fb4347a80fc SHA-1: 7c4afb4dc191f4233f7d13e7c84dddbe611f4cc9 SHA-256: 85878a9e14a459848bc1d829a686ab656673084c8069f2e5c04fc30c09c6eee4
196 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It contains numerous links to external PDFs hosted on compromised WordPress sites and disposable domains, suggesting it functions as a link farm for SEO poisoning or to distribute further malware. The heuristic 'SE_REMOTE_SUPPORT_LURE' indicates the document likely attempts to trick the user into installing or running remote support software, a common pretext for malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9957

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Remote-support tool lure high SE_REMOTE_SUPPORT_LURE
    Document instructs the user to install, open, or connect with a remote-support tool such as AnyDesk, TeamViewer, Quick Assist, or ScreenConnect — high-risk in an unsolicited document
  • 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://regmac.net/userfiles/files/tebinujesixudirev.pdf In PDF document text
    • http://brezov-gaj.si/uporabnik/file/nexinamalopamovagov.pdfIn PDF document text
    • http://momsystem.ru/public/file/55374875446.pdfIn PDF document text
    • https://www.brunosistemi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b2e5df58827---zapotukupam.pdfIn PDF document text
    • http://fullx.net/files/50529436826.pdfIn PDF document text
    • http://ngpsusa.com/wp-content/plugins/super-forms/uploads/php/files/lmsdnr2kekeupvk8aumtf0h7sq/memivowob.pdfIn PDF document text
    • http://www.britocunhaadvocacia.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/160a0f228f422a---favozitedudemuwopu.pdfIn PDF document text
    • http://crmloccitanecr.com/campannas/file/rakukumafepumoxala.pdfIn PDF document text
    • http://asesoriagarpe.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098a4f51c825---xefolulud.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160eda1de2cbcc---36010676135.pdfIn PDF document text
    • https://ethiquedevelopers.com/wp-content/plugins/super-forms/uploads/php/files/affc272eb80fb4dc55dfa92a6335340d/vuribodowewufelomiwutux.pdfIn PDF document text
    • https://area34.info/wp-content/plugins/super-forms/uploads/php/files/oh0sbdvq41k5v0ehvbbeujcrt7/dafifujigemokegitavonelof.pdfIn PDF document text
    • http://regmac.net/userfiles/files/92299261438.pdfIn PDF document text
    • http://krajinar.cz/soubory/files/besuxekebugu.pdfIn PDF document text
    • http://fittbike.hu/files/file/57352401763.pdfIn PDF document text
    • http://friluftsgruppen.se/wp-content/plugins/formcraft/file-upload/server/content/files/160d496dcbee87---10087080041.pdfIn PDF document text
    • https://www.autodepotperformancegroup.ca/wp-content/plugins/super-forms/uploads/php/files/okmkvuakg3rc6hjhb7osa675f5/sipamilupera.pdfIn PDF document text
    • http://allseasonsart.com/uploads/fck_uploads/file/tanowew.pdfIn PDF document text
    • https://gfow.om/wp-content/plugins/super-forms/uploads/php/files/kum082e9pspuo5ubn8unn3jber/45450012582.pdfIn PDF document text
    • http://abapaposentados.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607ec31a51c4e---bekaji.pdfIn PDF document text
    • http://home-hj.com/up_photo/file/pibira.pdfIn PDF document text
    • https://parkettworld.com/upload/files/dekesazifenovumi.pdfIn PDF document text
    • http://medicapoland.pl/uploaded/file/71494031143.pdfIn PDF document text
    • http://onlytech-tunisie.com/userfiles/file/16993908441.pdfIn PDF document text
    • https://protectname.xyz/whoisprivacy/userfiles/files/jepuvejepawifasirib.pdfIn PDF document text
    • https://amalighting.com/wp-content/plugins/super-forms/uploads/php/files/84b308215de3348d8ec071eb24d45745/11074695045.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=pokemon+xy+para+gba+en+espa%C3%B1ol+descargarPDF link annotation
    • 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_off0000e359.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE359 18388 bytes
SHA-256: 51c17ee37664b90b817a013782f7dca00949f737f769417bc0e52bc539255346
font_01_sfnt_off00011202.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11202 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012a19.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12A19 11324 bytes
SHA-256: c3c693f2ca78778f28ca15c2a26c39ff764bfdfe3a3cc0468d01b4c6e67e71af