Malicious PDF — malware analysis report

Static analysis result for SHA-256 368fa27cbfd7ea53…

MALICIOUS

PDF

81.5 KB Created: 2021-09-08 12:25:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 3d1a4253c13b54b8342d5c1dd277d1aa SHA-1: 4c2b1c9099c7db29c52eb8be2ee287b4a8f92175 SHA-256: 368fa27cbfd7ea531a5d343011f5450d93ebc6bb0aa073b92f0bc4485eef49e2
156 Risk Score

Malware Insights

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

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The document body is heavily obfuscated and unreadable, providing no direct clues about its purpose beyond what the heuristics indicate.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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 http://www.florentmaussion.net/userfiles/File/leripoxanul.pdf In PDF document text
    • http://baanpowertrain.com/wp-content/plugins/formcraft/file-upload/server/content/files/161380329aa0da---64946557513.pdfIn PDF document text
    • http://dhf-china.com/d/files/75765664457.pdfIn PDF document text
    • https://cytairtool.com/test/userfiles/file/20210908_60193.pdfIn PDF document text
    • https://www.medicalbi.com/ckfinder/userfiles/files/49730728443.pdfIn PDF document text
    • http://regcureguide.com/files/files/58201850660.pdfIn PDF document text
    • http://cellesekorea.com/ckupload/files/73020751626.pdfIn PDF document text
    • https://morganmethod.tuesdaytrader.com/ci/userfiles/files/wulejipififowowef.pdfIn PDF document text
    • https://smoothnomad.com/wp-content/plugins/super-forms/uploads/php/files/i79u1d5l1i0g8a49cmphnc0h6i/52655678602.pdfIn PDF document text
    • http://ahnil.com/userData/board/file/26026828113.pdfIn PDF document text
    • http://extrastyle.ee/ckfinder/userfiles/files/wavaga.pdfIn PDF document text
    • http://finchamauto.com/pics/11649092975.pdfIn PDF document text
    • https://arhometutor.com/userfiles/file/74743581022.pdfIn PDF document text
    • http://www.carolglassman.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613453066c820---fumojegepo.pdfIn PDF document text
    • http://chothuethietbi.info/img/files/3709317668.pdfIn PDF document text
    • http://e-motyle.natura2000.pl/imgturysta/files/40452174364.pdfIn PDF document text
    • https://tootooair.com/FileData/ckfinder/files/20210904_A556145F3BB390E7.pdfIn PDF document text
    • http://zhengfutz.com/v15/Upload/file/202198046224931.pdfIn PDF document text
    • http://gz-chengeng.com/uploadfile/files/10047239361.pdfIn PDF document text
    • https://pioneerlift.com/upfiles/editor/files/nisowitow.pdfIn PDF document text
    • http://audiomaster.se/wp-content/plugins/formcraft/file-upload/server/content/files/16131f7c2b90f6---sotusevuzudibeti.pdfIn PDF document text
    • http://medica-eg.com/userfiles/file/sonimopiminujaturunixuv.pdfIn PDF document text
    • http://chandravanshi.com/userfiles/file/76596330882.pdfIn PDF document text
    • http://everestlodgelukla.com/userfiles/file/zeloxuvajegaz.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=pentair+rebel+cleaner+manualPDF link annotation
    • http://alessandrotria.altervista.org/areap/ckfinder/userfiles/files/77018527355.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_off0000d839.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD839 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f04b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF04B 18676 bytes
SHA-256: ae82b7b1253cc0b0daa561fd601197a622171021034fcf4892d7f65c0dac181a
font_02_sfnt_off000120f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120F9 10344 bytes
SHA-256: b8c96436b158f86215114d94614fb4471d736a64717f1dbbbde10c8c18d329cd