Malicious PDF — malware analysis report

Static analysis result for SHA-256 0a81f418453de418…

MALICIOUS

PDF

90.5 KB Created: 2021-09-16 11:51:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: c78dc025264a4d9adad682f68af838ee SHA-1: d5f61a8c30e91339e6562cce0b4511d55b373303 SHA-256: 0a81f418453de4186d97fbac7b34cec057b45391ddd4ddb9df49b105ed0df8d8
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with numerous URLs pointing to potentially compromised or disposable hosting sites. The primary attack pattern involves directing users to these external sites, likely for phishing or to download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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://hasdeu.md/data/userfiles/files/gixogewovimupunad.pdf In PDF document text
    • https://tectrongim.com/uploads/file/29363424830.pdfIn PDF document text
    • https://binarbaidservices.com/public_html/userfiles/file/23354267398.pdfIn PDF document text
    • https://anakmeong.com/contents/files/76675064265.pdfIn PDF document text
    • http://sibleyestateplanning.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/bagur.pdfIn PDF document text
    • https://rgcsmt.org/ckfinder/userfiles/files/36489711731.pdfIn PDF document text
    • http://champaigncursillo.com/userfiles/file/62022272436.pdfIn PDF document text
    • https://ecohort.com/userfiles/files/37979547403.pdfIn PDF document text
    • http://hzjksj.com/images/upload/File/73267537256.pdfIn PDF document text
    • http://proxkimya.com/resimler/files/nogugodezumozir.pdfIn PDF document text
    • http://tlznailspa.com/media/files/faxib.pdfIn PDF document text
    • http://kyea.org/imageuploads/13402092820.pdfIn PDF document text
    • http://skalamatbaa.com/userfiles/file/witavovitu.pdfIn PDF document text
    • http://dubilex.com/userfiles/files/vozulegifatos.pdfIn PDF document text
    • http://maxitelt.no/wp-content/plugins/formcraft/file-upload/server/content/files/1613d33309a1c4---nudibaxidopa.pdfIn PDF document text
    • http://viaterrestre.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16142902779555---fipoxorivilawafafepa.pdfIn PDF document text
    • http://thegioichuyendong.info/app/webroot/upload/files/wulobebagurefol.pdfIn PDF document text
    • http://sgpeo.pl/users/file/kexegaluxuzudovebozafaki.pdfIn PDF document text
    • http://es-umzuege-transporte.de/wp-content/plugins/super-forms/uploads/php/files/54723216dad74ef351f76a1d9163f4d4/49219719048.pdfIn PDF document text
    • https://fibra-optica.ro/ckfinder/userfiles/files/35178550395.pdfIn PDF document text
    • http://shannonlakeestates.org/fck_images/file/74094032574.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=night+of+the+demons+3+watch+onlinePDF 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_off0000fcd8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFCD8 17688 bytes
SHA-256: 005ddd5c01a5e57fc8e1bf93711537a9f0ecc32ee10e3500898c2397eb7d6a0c
font_01_sfnt_off00012a90.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12A90 11056 bytes
SHA-256: 1bbe9d331fa43cc442a0715014b659ff8cf4865f91171eeaa029dcc41fb29d40
font_02_sfnt_off0001440e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1440E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1