Malicious PDF — malware analysis report

Static analysis result for SHA-256 85813853565ee7db…

MALICIOUS

PDF

91.3 KB Created: 2021-09-16 18:11:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 2dbe07da8aefdbf1a67afde6053ff883 SHA-1: 4d8b5e816c0e7dd155e503186e9f37a97d375161 SHA-256: 85813853565ee7db0a511939e1cde14f1302f7c47c177167311ca2c47108e1ad
186 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. The critical heuristic 'SE_SECRET_RECOVERY_LURE' strongly suggests the document's purpose is to trick users into revealing sensitive recovery information, such as private keys or backup codes. The presence of numerous embedded URLs, many pointing to PDF files on potentially disposable domains, further supports a phishing or credential harvesting campaign.

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
  • 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.
  • 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://musicpark-live.com/userfiles/file/veveku.pdf In PDF document text
    • http://sipzip.com/userfiles/file/70262492139.pdfIn PDF document text
    • http://chukgoobok.com/files/fckeditor/file/44216205173.pdfIn PDF document text
    • http://ttlengenharia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16134e0de1dbe1---98875784588.pdfIn PDF document text
    • http://labellebeaute.com.hk/ckfinder/userfiles/files/7270273008.pdfIn PDF document text
    • https://webmedcentralplus.com/userfiles/file/51850364332.pdfIn PDF document text
    • https://hobbyschuurtje-webwinkel.be/images/userfiles/file/wegazadasiligaxojujaz.pdfIn PDF document text
    • http://exima.kr/userData/board/file/7237667782.pdfIn PDF document text
    • https://europawindow.com/app/webroot/img/main_content/files/zelakuxefatobizad.pdfIn PDF document text
    • http://greenlivinggarden.com/htdocs/UserFiles/file/92239672550.pdfIn PDF document text
    • http://herfon-machinery.com/images/ckfinder/files/20210912040503.pdfIn PDF document text
    • https://ises.ca/phpsites/vertical_living/uploads/file/veberupuzi.pdfIn PDF document text
    • http://ltmetal.com/userfiles/files/86391763628.pdfIn PDF document text
    • http://tofuyatogo.com/uploads/files/69180456183.pdfIn PDF document text
    • http://xn----8sbfeahwarn6ac1adp3fb2p.xn--p1ai/userfiles/file/82293481544.pdfIn PDF document text
    • https://nangluongvada.com/uploads/files/67622674070.pdfIn PDF document text
    • https://sapporomn.com/userfiles/files/wuxakatumavifofuzenire.pdfIn PDF document text
    • http://freeski.hu/freeski/file/62878211565.pdfIn PDF document text
    • https://idealist.ro/userfiles/file/junagijate.pdfIn PDF document text
    • https://xn--interpeas-r6a.es/upload/files/tesosudowev.pdfIn PDF document text
    • http://nsmpublicschool.org/slbdavbatala/userfiles/file/sutofotadebizuzurejujob.pdfIn PDF document text
    • http://paykaaluminiya.ru/ckfinder/userfiles/files/13135674622.pdfIn PDF document text
    • http://kraljicabih.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c8e553c8a7---36560308451.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=outlook+webmail+sign+inPDF 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_off00010011.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10011 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00011828.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11828 10792 bytes
SHA-256: e3fd0b917b86b3a6466d7d11b26443c3730e5989ffe052f9b3e6ba7ba9689b4b
font_02_sfnt_off00013116.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13116 18104 bytes
SHA-256: 1bd5b0077fa55f0b2542c67068e8a3ec4620388237ca429771e6875e531dd8d2