Malicious PDF — malware analysis report

Static analysis result for SHA-256 d5833efe5b308082…

MALICIOUS

PDF

80.9 KB Created: 2021-10-31 23:36:13 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 047fcf115b64738c860cf90decf1d9e5 SHA-1: 2bffb554a546f41e02f62c486fb588ce87c37b51 SHA-256: d5833efe5b3080827f256e5854f523814801365cdc79471d77e670c4c40b2264
146 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is a PDF document flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm and a callback phishing lure, prompting users to call a phone number under the guise of security or billing issues. While no scripts were directly extracted, the PDF structure and embedded URLs suggest it is designed to redirect users to malicious sites or initiate fraudulent phone calls.

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
  • 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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • 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 https://huntic.ru/uplcv?utm_term=baby+pluto+coloring+pages PDF link annotation
    • http://firesecurity.sk/userfiles/file/57221625470.pdfIn PDF document text
    • http://balatonfurediallatorvos.hu/userfiles/file/35492411096.pdfIn PDF document text
    • https://markyatirim.com/resimler/files/wanugoninuguridog.pdfIn PDF document text
    • http://lungshingcentre.com/userfiles/1204271003.pdfIn PDF document text
    • https://gmnavarra.es/ckeditor/files/50655443900.pdfIn PDF document text
    • http://twtqedu.com/userData/ebizro_board/file/pagixem.pdfIn PDF document text
    • https://godahoian.com/app/webroot/upload/files/supukibetivasixakugum.pdfIn PDF document text
    • http://kosmonautika.ee/ckfinder/userfiles/files/rokuwo.pdfIn PDF document text
    • http://cosmik-kinoteatr.ru/sadm_files/wiledexakevo.pdfIn PDF document text
    • https://drinkpoint.com/uploads/files/97633267776.pdfIn PDF document text
    • http://www.stratcareerservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/16158f6ce725fe---10461551022.pdfIn PDF document text
    • http://schokoladenfontaene.de/idata/pijoraxunabutotazavup.pdfIn PDF document text
    • http://royalvisas.com/fcs/userfiles/file/fidizarekebivogoxop.pdfIn PDF document text
    • http://unseretochter.com/images/file/foruro.pdfIn PDF document text
    • http://qianshunqs.com/admin/upload/kuvukorokurisix.pdfIn PDF document text
    • http://rencontres-icare.org/userfiles/file/boneleduweza.pdfIn PDF document text
    • http://indiebookoftheday.com/wp-content/plugins/formcraft/file-upload/server/content/files/161725fb7093a3---59556041231.pdfIn PDF document text
    • https://hongmao.tw/uploads/files/202110190755522283.pdfIn PDF document text
    • https://mabuksusu.com/contents/files/xafure.pdfIn PDF document text
    • http://ed-web.cz/userfilesfile/34746840672.pdfIn PDF document text
    • http://xn--80aafkatcapceshpicpg3h.xn--p1ai/pict/file/99592530843.pdfIn PDF document text
    • http://dyglas.com/userData/board/file/gafeziwatosed.pdfIn PDF document text
    • https://topclassgardening.nl/images/file/duwuzo.pdfIn PDF document text
    • http://studioriboldi.eu/userfiles/files/16790540872.pdfIn PDF document text
    • http://tunecharts.com/userfiles/file/30732726751.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_off0000d7ac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD7AC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000efbe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFBE 17308 bytes
SHA-256: bbf8732d01e11fbfdcbb3dce488c89f24b4839b6ee1e867c244d1db455eb1548
font_02_sfnt_off00011cb0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CB0 10956 bytes
SHA-256: ecc6479505a28e786144c5dee33814d48fbc4a81d65ee529ed97f762815ada7c