Malicious PDF — malware analysis report

Static analysis result for SHA-256 983cdc0cd60df823…

MALICIOUS

PDF

116.3 KB Created: 2021-06-21 10:36:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-29
MD5: cd0b5308d0960b454ec2b3ed3218083b SHA-1: a765e71b2c427fbd8992636894f6745f984e0708 SHA-256: 983cdc0cd60df8231acd253af983759c84fb4b55a8132f6e804dd2405984aa5b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous external URIs and links to compromised WordPress upload storage, suggesting it functions as a link farm to distribute malicious content or phish users. The presence of embedded URLs and the nature of the heuristics point towards a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://crysiq.ru/uplcv?utm_term=why+do+artists+make+portraits PDF link annotation
    • http://www.virtualaid.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16079ee06da88b---58341133361.pdfIn PDF document text
    • http://lookupagency.es/wp-content/plugins/formcraft/file-upload/server/content/files/1607569017a02a---sumuvifab.pdfIn PDF document text
    • https://collegemahan.ir/basefile/collegemahanir/files/magitisejuguwageti.pdfIn PDF document text
    • http://luckyassessoria.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b842107edf7---zuzalixafax.pdfIn PDF document text
    • http://resetimpianti.it/reset/public/file/18756853365.pdfIn PDF document text
    • http://www.homefacelifters.com/wp-content/plugins/super-forms/uploads/php/files/2cbaa0069b6085e8d010308c86229b62/48648957357.pdfIn PDF document text
    • http://kino-profi.com/wp-content/plugins/super-forms/uploads/php/files/bf135128a3312f46c77d844bac8cfd0f/pirelorotevipuwegi.pdfIn PDF document text
    • http://kraljicabih.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e9a7b826f7---tenabelavinupofulopun.pdfIn PDF document text
    • https://vmkstroi.ru/wp-content/plugins/super-forms/uploads/php/files/cbd023fcb694ab59606f6516b362692c/2253305481.pdfIn PDF document text
    • http://structurecreative.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aeac6659e9b---bugofilegebemejujo.pdfIn PDF document text
    • http://kartywspomnien.pl/uploads/assets/file/57318245949.pdfIn PDF document text
    • https://www.isgs.org/wp-content/plugins/super-forms/uploads/php/files/638a6c6cd0647dc8a41bb2dad563c422/77720553352.pdfIn PDF document text
    • http://au-coeur-du-temps.com/userfiles/file/74358746708.pdfIn PDF document text
    • http://mopron.ru/upload/files/22029525221.pdfIn PDF document text
    • https://www.marthatrotts.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160a73bb613b6c---95949151350.pdfIn PDF document text
    • http://melissajacksonmd.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a6d363eb074---misefiloxubiputafufovexi.pdfIn PDF document text
    • http://marty-triple-m.ch/inhalt/files/45022505145.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001836b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1836B 5344 bytes
SHA-256: 550fa1077785ced369f6b52f26bb76002c5769e37ef2df91affd373d6b920cd7
font_01_sfnt_off00019582.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x19582 15444 bytes
SHA-256: 2fcac4b57172e5c454f13204d6503656885737241cbb12def9b82f98fedbd164