Malicious PDF — malware analysis report

Static analysis result for SHA-256 e4a289e6f0845ad0…

MALICIOUS

PDF

76.1 KB Created: 2021-09-20 15:37:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: fe982a38c20c9943fe020fc90630429a SHA-1: a2981f65f4462565e0e8dee71790bdd647cf97f4 SHA-256: e4a289e6f0845ad0d36d3a2f934cad563ddbcf09d6705dae735aea9a8957b840
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The file is identified as malicious by ML classifiers and ClamAV, specifically as a phishing trojan. Numerous heuristics indicate the PDF functions as a link farm, directing users to compromised WordPress uploads and other disposable hosting sites. The embedded URLs, such as https://laborke.ru/uplcv?utm_term=fifa+18+mod+14, are likely used to distribute further malicious content or conduct phishing attacks.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

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://laborke.ru/uplcv?utm_term=fifa+18+mod+14 PDF link annotation
    • http://tdsns.ru/userfiles/file/xamotufijojesaxogonuwive.pdfIn PDF document text
    • http://3sdent.com/upload/files/35501704871.pdfIn PDF document text
    • http://0vote.com/ckfinder/files/72812745311.pdfIn PDF document text
    • https://detectiveoffice.net/userfiles/file/53263669498.pdfIn PDF document text
    • https://pieseautocomenzi.ro/userfiles/file/16341180802.pdfIn PDF document text
    • https://nevisnews.com/userfiles/34941539179.pdfIn PDF document text
    • http://bienbao.net/uploads/files/buwelimifabid.pdfIn PDF document text
    • http://americasbestmanassas.com/uploads/files/wobovipatofes.pdfIn PDF document text
    • https://artbynela.com/uploads/file/gimuke.pdfIn PDF document text
    • http://skolky.info/foto/images/file/dumesolipisavap.pdfIn PDF document text
    • http://visualpaint.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130420047ec1---18627509083.pdfIn PDF document text
    • https://toptenstudy.com/upload/files/BodyFile__613D8A779B399.pdfIn PDF document text
    • https://bomando.bomsolar.com/uploadfiles/files/36360744765.pdfIn PDF document text
    • http://rigdrilling.org/userfiles/file/56833024702.pdfIn PDF document text
    • http://cinstech-inspect-survey.com/fckeditor_userfiles/file/87619918901.pdfIn PDF document text
    • http://chrisdepanneservices.fr/Sites/cds/files/vesopakazuleluranomumam.pdfIn PDF document text
    • https://www.tratedu.net/ssss2018/assets/143ad273/ckfinder/core/connector/php/upload/userfiles/files/8d5836b1de3d5ea2fffee72f9fd0aa7a.pdfIn PDF document text
    • http://theydeserveastamp.org/wp-content/plugins/formcraft/file-upload/server/content/files/1613f77057080d---78795478618.pdfIn PDF document text
    • http://iburgisidimarsala.eu/userfiles/files/wiwikudiz.pdfIn PDF document text
    • https://tfnd.org/wp-content/plugins/super-forms/uploads/php/files/10e93ebc2f8f1fd958432b984be221e5/rijupajimagunegoluzasufo.pdfIn PDF document text
    • http://tverzhilservis.ru/foktver.ru/ckfinder/userfiles/files/66261870426.pdfIn 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://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_off0000c0ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC0FF 19816 bytes
SHA-256: d5f752de05d42ae750b605ccc14a4a7b534b3e7bb5bf9d82ffafa24a11a51bcb
font_01_sfnt_off0000f4a5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4A5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010cbc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10CBC 10184 bytes
SHA-256: fe58e06e78d5e10380201bc320a011802f13f9aa58b736cc9d91adfcf61a38e5