Malicious PDF — malware analysis report

Static analysis result for SHA-256 f392d1eba3c8e0bb…

MALICIOUS

PDF

81.1 KB Created: 2021-09-02 14:27:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 3c942fc2fa79bdafb47f4949f844bcb2 SHA-1: da00405543131496cc577df6eb16148530073ed4 SHA-256: f392d1eba3c8e0bb5f85b2fcc9ae09bdaa59f7836a43144a57bc44e944c0def0
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as Pdf.Phishing.Trojan. The document contains a link farm pointing to compromised WordPress upload storage, suggesting an attempt to distribute malicious content or conduct phishing. The presence of embedded URLs and the nature of the heuristics indicate that the primary function is to redirect users to potentially harmful external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

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 http://www.majorisinvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16093e512b8411---jumixudo.pdf In PDF document text
    • https://rmissio.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16110065763771---gidupanewumoxozulugelil.pdfIn PDF document text
    • https://f1com.ge/wp-content/plugins/super-forms/uploads/php/files/c574ea448b7d446e6191b3baae6716b4/moriboxegimalugunefinax.pdfIn PDF document text
    • http://work4shop.cz/userfiles/file/17828392882.pdfIn PDF document text
    • https://ikima.fr/uploads/file/33173516532.pdfIn PDF document text
    • http://opalbiosciences.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608324824963c---zafasusowu.pdfIn PDF document text
    • https://xn--80ag1a2a.xn--p1ai/files/file/nexiwuduvububemapaw.pdfIn PDF document text
    • https://www.partyshuttlebus.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16095d61ccf9e2---fafafunemudibivuloxepiv.pdfIn PDF document text
    • https://mymovingestimate.com/wp-content/plugins/super-forms/uploads/php/files/50d191302d3a2f66d3f782a5d81fb845/wedufexuba.pdfIn PDF document text
    • http://exactblue.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609f4f8ed6b58---48405980177.pdfIn PDF document text
    • http://www.giuseppe.ru/ckfinder/userfiles/files/20919641692.pdfIn PDF document text
    • http://dochoiotovn.com/uploads/userfiles/file/nimadomu.pdfIn PDF document text
    • http://aeskulap24h.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cb82cac3831---74521937665.pdfIn PDF document text
    • http://www.orhancoskun.com/wp-content/plugins/formcraft/file-upload/server/content/files/160743b5f32c0d---16963123292.pdfIn PDF document text
    • http://csc0451.com/userfiles/file/20210805234905_zw54ce.pdfIn PDF document text
    • http://peoplefoster.com/pliki/widiwixotenusuzade.pdfIn PDF document text
    • http://wbbray.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ade9e57dadf---72605040131.pdfIn PDF document text
    • http://webatnet.de/ckfinder/userfiles/files/64556751398.pdfIn PDF document text
    • http://call.ae/wp-content/plugins/formcraft/file-upload/server/content/files/160855c2fb7df5---66277903982.pdfIn PDF document text
    • http://le383.com/uploads/files/28688730007.pdfIn PDF document text
    • http://phaptangpgvn.net/app/webroot/upload/files/46594077263.pdfIn PDF document text
    • https://www.getfitcrew.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609229d784ae0---28190185086.pdfIn PDF document text
    • http://andreagarciam.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c7a8b2e6fb---dirudoxegarepasupitu.pdfIn PDF document text
    • https://www.casestilistas.es//ckfinder/userfiles/files/81474834539.pdfIn PDF document text
    • https://www.adcgrain.com/wp-content/plugins/super-forms/uploads/php/files/48bfc56b331deae18e2bce714721846e/71209254781.pdfIn PDF document text
    • https://choiceenergynetwork.com/wp-content/plugins/super-forms/uploads/php/files/f5fb8983e21a55f370a152b82123e021/90367464344.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=balloon+rocket+lab+worksheetPDF 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_off0000d903.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD903 10608 bytes
SHA-256: 5696d4147f75b5e0c3a9cc6661077264288fd541eefd87c13a6d742b5b995700
font_01_sfnt_off0000f154.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF154 17328 bytes
SHA-256: d3de4f8b3e715ce17218ac14c949dfa6d5c178e99abb9842a0543a96d8b94b80
font_02_sfnt_off00011e06.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E06 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1