Malicious PDF — malware analysis report

Static analysis result for SHA-256 02c161ade53bc759…

MALICIOUS

PDF

77.5 KB Created: 2021-02-08 18:53:36 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-22
MD5: bf08926145d740108f67f15f21f8595f SHA-1: d19f8b58747f3b62aab8f61b22248c6e06afb17b SHA-256: 02c161ade53bc7596bb020c53a3c8db76a9f6da4639a1933dec258af3c63e22d
184 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains multiple embedded URLs, with at least one identified as a malicious redirector. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to phish or deliver a secondary payload. The document body's reference to a 'critical ops mod apk update' serves as a lure to encourage users to click the malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 5

  • 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 links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • 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://yafferge.ru/aws?utm_term=critical+ops+mod+apk+update In PDF document text
    • http://tasimidu.iblogger.org/fortnite_challenges_cheat_sheet_week_2.pdfIn PDF document text
    • http://vasowenotaruso.22web.org/printable_math_worksheets_for_3rd_graders.pdfIn PDF document text
    • http://tifubuza.22web.org/wnyc_app_android.pdfIn PDF document text
    • http://gedawuxofawu.iblogger.org/box_spring_cover_sheet.pdfIn PDF document text
    • http://bimiwefumukiv.22web.org/pidedodavevubetavazu.pdfIn PDF document text
    • http://nufogikije.22web.org/bengali_typing_software_free_for_android.pdfIn PDF document text
    • http://lemixebu.22web.org/boot_camp_version_6._1.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://gagisomix.rf.gd/5475354416.pdfIn PDF document text
    • https://s3.amazonaws.com/wunojipu/najom.pdfIn PDF document text
    • http://fasevebozumip.rf.gd/kabusenosi.pdfIn PDF document text
    • http://wetafemef.epizy.com/wopomolaxevesuwivafutono.pdfIn PDF document text
    • https://s3.amazonaws.com/gitipelut/vunarugubevamatonirituwup.pdfIn PDF document text
    • http://lazunebenak.epizy.com/86785553186.pdfIn PDF document text
    • http://nidemavaguwagev.rf.gd/lake_lavon_fishing_report_2018.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://scripts.sil.org/OFLIn 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_off0000ddd0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDD0 5188 bytes
SHA-256: 5536eba6c19d40f36d7e3d266c2bca24446b9da16eaea3921d56be35ec00f600
font_01_sfnt_off0000ef58.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF58 10756 bytes
SHA-256: 7963da42ab11919faa36caa8e163b3e050c81491ac830f008ec0f57e873b98aa
font_02_sfnt_off00011416.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11416 16136 bytes
SHA-256: 6bd6cda04696584186cf1917ebb65d70a28576a2cf09a71ff67a2fb08a026c5c