Malicious PDF — malware analysis report

Static analysis result for SHA-256 d1812055d009c078…

MALICIOUS

PDF

67.9 KB Created: 2021-10-01 13:22:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 00389d54302a4b3d5729b7c559ace01a SHA-1: 9e8d4b917217dd4d15875bb74666a6811913edfb SHA-256: d1812055d009c078d9115f4feac931340496e9cf01aa5ecaba6ecf660e360446
156 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm designed to redirect users to potentially malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://hillsdalehorseboarding.com/ckfinder/userfiles/files/31628305893.pdf In PDF document text
    • http://autosoftware.company/autoresponders_images/files/36419754309.pdfIn PDF document text
    • https://stpm-sa.com/userfiles/file/rekuwip.pdfIn PDF document text
    • https://gea99.com/ckfinder/userfiles/files/dutebipafegomolevoxa.pdfIn PDF document text
    • http://robwalker.net/fckupload/file/74098426644.pdfIn PDF document text
    • http://www.mondzorgvesa-voorschoten.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16139e66028b6d---19219460180.pdfIn PDF document text
    • https://sv-fin.ru/wp-content/plugins/super-forms/uploads/php/files/360228e89d039d49f7db2436c6c222a1/70362335469.pdfIn PDF document text
    • http://dintainoodle.com/uploads/files/wavebobimebijuleb.pdfIn PDF document text
    • http://kingtonkatsu.com/uploads/files/80209351749.pdfIn PDF document text
    • http://texmet.pl/userimages/file/zuruzad.pdfIn PDF document text
    • https://ecohort.biz/userfiles/files/64727493019.pdfIn PDF document text
    • https://metroguards.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1613210edc557c---pagujepinuma.pdfIn PDF document text
    • http://metallpress.info/files/55333739974.pdfIn PDF document text
    • http://ttlengenharia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16140ed7633acc---potasalalupiva.pdfIn PDF document text
    • http://www.taxivanclass.com/uploads/ckfinder/files/79163061164.pdfIn PDF document text
    • https://mepho.hu/ckfinder/userfiles/files/xeposi.pdfIn PDF document text
    • http://peter-scherer.de/userfiles/file/xoxumezaruzugez.pdfIn PDF document text
    • http://faurau.com/luodan/images/userfiles/file/jonoto.pdfIn PDF document text
    • http://www.videocopilot.net/assets/public/ckfinder/userfiles/files/10382318831.pdfIn PDF document text
    • https://repairbase.net/FCKeditor/editor/filemanager/connectors/php/images/file/11870814387.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=what+is+ndkPDF 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_off0000ab8e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAB8E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c3a5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC3A5 10032 bytes
SHA-256: 62a12ef17294f234b382bea79a0b573168fc43f11e875ba81424b1b130d303fd
font_02_sfnt_off0000d9d9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9D9 15952 bytes
SHA-256: fd90a0e22f816c8db999b6cfd09e8cac7d6c7ab70304502c80afd39eb23929b8