Malicious PDF — malware analysis report

Static analysis result for SHA-256 4bbbf157fb278644…

MALICIOUS

PDF

79.6 KB Created: 2021-03-30 12:39:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: ac3880d11e0baef7623dfd86dee4442f SHA-1: 904d18a57f76cc35e6642553e062fc390cb0ab1c SHA-256: 4bbbf157fb2786446f75a148c34107a2d7ae4674ece21eec3c6a2cf9b030db05
166 Risk Score

Malware Insights

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

The file is a PDF document flagged as malicious by ClamAV and an ML classifier. It contains multiple embedded URLs, with at least two identified as suspicious or potentially malicious lures. The PDF_SUSPICIOUS_LINK_LURE heuristic indicates invisible links pointing to suspicious domains, suggesting an attempt to trick users into visiting malicious sites. While no scripts were explicitly extracted, the nature of the embedded links and the 'Phishing.Trojan' detection strongly suggest a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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
  • Image-heavy PDF with invisible link to suspicious domain high PDF_SUSPICIOUS_LINK_LURE
    PDF is a small image-heavy lure with invisible link annotations that send the user to a suspicious high-risk-domain URI. This matches credential-phishing carriers where the visible document is only a prompt and the real collection flow happens on the linked website.
  • 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 https://dafemum.ru/wix?keyword=the+ex+games+part+3+pdf
    • http://com-login8.xyz/lafulal96p34.pdf
    • http://silkhfig.bid/tn_school_teachers_attendance_appv0ecv.pdf
    • https://static.s123-cdn-static.com/uploads/4376870/normal_60005871437f9.pdf
    • https://static.s123-cdn-static.com/uploads/4369930/normal_5fdf7949be8b5.pdf
    • https://cdn-cms.f-static.net/uploads/4468563/normal_60292aed497d5.pdf
    • https://cdn-cms.f-static.net/uploads/4447649/normal_60604821b641d.pdf
    • https://static.s123-cdn-static.com/uploads/4422144/normal_5ff94900b7714.pdf
    • https://static.s123-cdn-static.com/uploads/4373519/normal_5fed3a510f393.pdf
    • http://nageramuvepom.mywebcommunity.org/66924318804.pdf
    • https://cdn-cms.f-static.net/uploads/4486537/normal_603a8cf9dbdde.pdf
    • http://usacreditmonitoring.info/who_invented_the_basketball_game_brainlyimtnl.pdf
    • https://cdn-cms.f-static.net/uploads/4387925/normal_6014665361065.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://www.daltonmaag.com/
    • https://69c5641f-197a-42c1-bef1-daa502c1f1d7.filesusr.com/ugd/948cea_1e0d8c8970c14d12981d32b35579b62a.pdf?index=true
    • https://uploads.strikinglycdn.com/files/c3f165bc-6b32-4975-99e9-fd2fdbfffa65/semifokitabufogiwu.pdf
    • https://144ece88-722e-4d59-a9d1-ae16887514c2.filesusr.com/ugd/48b17f_f031c5e4a954470c8c6c2f0d4364f35a.pdf?index=true
    • https://uploads.strikinglycdn.com/files/28896139-cdcb-47c6-a4d3-3b996e65ec99/english_vocabulary_list_by_category.pdf
    • https://1237a3da-0b33-4890-9ba9-974507bf2590.filesusr.com/ugd/3e0cb9_af7b18df45af4ec68b7de1d000766037.pdf?index=true
    • https://8c77b9b7-c39b-43d6-9406-6086bd2c0f93.filesusr.com/ugd/ee6770_7e42dbf37b5843af8e2e55e6639c9e38.pdf?index=true
    • http://kikukuvikato.myartsonline.com/english_language_paper_1_revision.pdf
    • http://pulutugorivexek.atwebpages.com/abdominal_exercises_free_download.pdf
    • http://jabejanaboz.atwebpages.com/33036106311.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000eb93.bin
d1c0f5af7ddbb68b209a6e93da9ad881e4eeec5cf24ce0c947f28d900a39c70d
pdf-font-stream PDF embedded font (sfnt) at offset 0xEB93 5128 bytes
font_01_sfnt_off0000fd09.bin
a5ed9e6c615fdf096511ecce2c656c2cbf61e7161a7822b028aef071d77e0806
pdf-font-stream PDF embedded font (sfnt) at offset 0xFD09 11304 bytes
font_02_sfnt_off0001236b.bin
7f6049e5011acf0e8581793f2bc2bb947aac2929fdb77abc318b2a6155c1ef71
pdf-font-stream PDF embedded font (sfnt) at offset 0x1236B 4324 bytes