Malicious PDF — malware analysis report

Static analysis result for SHA-256 fb83b846dd6628e5…

MALICIOUS

PDF

84.5 KB Created: 2021-09-13 16:06:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 9fe855457646e901a0269e014b5422e4 SHA-1: fb7b3b8f85f451fb576e0a282e2048ce9f704c89 SHA-256: fb83b846dd6628e549c050f46206ed31ba679e91cb06979ffc1b5acffc121d50
194 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and is flagged by ML classifiers and ClamAV as malicious. A critical heuristic indicates it's a 'Recovery secret / private key request' lure, aiming to phish for sensitive user credentials. The document also acts as a link farm, directing users to various PDF files hosted on potentially disposable domains.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Recovery secret / private key request critical SE_SECRET_RECOVERY_LURE
    Document requests recovery phrases, private keys, backup codes, or saved passwords. Requests for these secrets in a document are high-risk.
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://ariogalospspc.lt/userfiles/file/tarez.pdf In PDF document text
    • http://sl-light.ru/design/img/upload/file/85337027581.pdfIn PDF document text
    • http://mobil-tech.com/files/1998385786.pdfIn PDF document text
    • http://modernplating.com/userfiles/file/meroxuwejuwutasesaxuge.pdfIn PDF document text
    • http://abwcrainhwy.com/uploads/files/9810524987.pdfIn PDF document text
    • https://triosms.com/userfiles/file/fepudowufemomatotowem.pdfIn PDF document text
    • https://vietnam-pump.com/userfiles/file/zinaj.pdfIn PDF document text
    • https://tyeetomsfishing.com/userfiles/file/32961300404.pdfIn PDF document text
    • http://knowleangling.co.uk/ckfinder/userfiles/files/90127978416.pdfIn PDF document text
    • http://rhondachem.com/d/files/14887042273.pdfIn PDF document text
    • http://fourfoods.com/images/files/96269668093.pdfIn PDF document text
    • https://stgeorgedentalcare.in/ckfinder/userfiles/files/duxukuwanevotugi.pdfIn PDF document text
    • https://lacgl.org/upload/editor/file/tujozitagop.pdfIn PDF document text
    • http://alfavit.tv/userfiles/file/43274611228.pdfIn PDF document text
    • https://www.helpfulhunks.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1613b65e6b315a---bigezakofesewopunakomufa.pdfIn PDF document text
    • http://myphamhelios.vn/luutru/files/tifasesepobaxutemaj.pdfIn PDF document text
    • http://3e3i.com/UserFiles/file///688683223.pdfIn PDF document text
    • http://wych123.com/upload/files/19574554703.pdfIn PDF document text
    • http://sherwoodonionfestival.com/ckfinder/userfiles/files/todok.pdfIn PDF document text
    • http://terminsk.by/pics/files/muxebemafolopisiwosorara.pdfIn PDF document text
    • http://antik-cafe-bergen.de/wp-content/plugins/formcraft/file-upload/server/content/files/16133332c7af1b---29284776250.pdfIn PDF document text
    • http://pivotal-technologies.com/userfiles/file/rawiri.pdfIn PDF document text
    • https://newchat.xyz/js/ckfinder/userfiles/files/58957567255.pdfIn PDF document text
    • http://21cedu.com/pds/userfiles/files/87669650436.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=android+secret+apkPDF 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_off0000df85.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF85 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f79c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF79C 10532 bytes
SHA-256: f1200f312e901257bb4eabe72acdb452c0fa9c36d10db927dc46eaf21eeb1817
font_02_sfnt_off00010fc3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10FC3 20192 bytes
SHA-256: d3543caf52f5ae2d32bf8666934efc28d76cfe8a140b775ec076a06fed3a9052