Malicious PDF — malware analysis report

Static analysis result for SHA-256 f7c586e4c15faf4e…

MALICIOUS

PDF

93.1 KB Created: 2021-03-30 19:35:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-13
MD5: 1b2f95141dd824799549ad9d810b2d5e SHA-1: f5c41046912dd9d01fed93c9f5ecfcc9ea813387 SHA-256: f7c586e4c15faf4e2604c64ac97f04cfce4a75ea4494f5f437ed520eb6eb8136
126 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics, including a critical ClamAV detection for 'Pdf.Phishing.Trojan' and an ML classifier indicating high maliciousness. The presence of numerous external URIs, some pointing to disposable hosting and employing UTM parameters, suggests a phishing or malware distribution attempt. The document body, though heavily obfuscated, contains references to a textbook and the authoring application, which may be part of a lure to disguise malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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
  • 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://zajinet.ru/strik?utm_term=nelson+textbook+of+pediatrics+20th+edition+pdf PDF link annotation
    • https://cdn.sqhk.co/vimexuda/ichnqCP/hatsune_miku_2d_live_wallpaper_apk.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4453551/normal_5fcc0c00a191b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4418970/normal_60418414d26b8.pdfIn PDF document text
    • https://cdn.sqhk.co/laruxibut/nNJjghe/auto_wallpaper_changer_apkpure.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4410207/normal_5feb2c56cca52.pdfIn PDF document text
    • https://cdn.sqhk.co/takejirasomu/fjceNih/ielts_full_listening_test_2018_with_answers.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4414680/normal_604e452f254d0.pdfIn PDF document text
    • https://cdn.sqhk.co/rowagana/hgjbidj/vezubekesaruf.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4473971/normal_5ff12f66c1664.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://nositejijo.epizy.com/.pdfIn PDF document text
    • https://s3.amazonaws.com/zodawanuror/80425997436.pdfIn PDF document text
    • https://d190c387-1498-4382-a59e-98d1a0a9794c.filesusr.com/ugd/a91264_7e1aa925d89e4033bb7f63701a61b64c.pdf?index=trueIn PDF document text
    • https://47e244ab-6b1f-4ae7-97e8-86de5b619f9f.filesusr.com/ugd/e1d12c_48cbbadd723444719b59eff26f056e54.pdf?index=trueIn PDF document text
    • http://jepitatumezelo.epizy.com/54887673961.pdfIn PDF document text
    • https://e05653fc-386e-4c8b-889d-738aee72c63e.filesusr.com/ugd/62421a_047ed261cb0c45a7a9fe3d2d3a72cf1b.pdf?index=trueIn PDF document text
    • https://3ced707c-20bd-49bb-93f1-edb15be4e391.filesusr.com/ugd/e90305_82f10fcc276b4f1abe81d5f4a36b716f.pdf?index=trueIn PDF document text
    • http://vumupekosevi.rf.gd/53139775989.pdfIn PDF document text
    • https://891dfe3a-8969-4df2-b253-5ccc4ebbb7a0.filesusr.com/ugd/e66789_d640f7d6602d4f78bb195a442fef3819.pdf?index=trueIn PDF document text
    • https://2a07c75e-e898-48ba-b326-4cccc82d0599.filesusr.com/ugd/ff154e_de849e7bfe954a3eb11431a20fd15855.pdf?index=trueIn PDF document text
    • https://ad060920-74d0-4a59-a46a-f478898ed72a.filesusr.com/ugd/a7c1e6_b6ccb8c8d84446de858aed1fc3c6c1bc.pdf?index=trueIn PDF document text
    • http://zifawikixeliba.epizy.com/kokokaxim.pdfIn PDF document text
    • https://s3.amazonaws.com/vuliwisuwig/kingdom_hearts_3_keyblades_guide.pdfIn PDF document text
    • https://9c789f27-b70c-4c9d-9e83-211ee8f99b38.filesusr.com/ugd/bdeb4c_32773b8bcd5549e8a7e611dc59958da8.pdf?index=trueIn 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

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00012d27.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D27 5760 bytes
SHA-256: 5bd85c113b44a79eed60e4f19a89f0c2b9aef0107f081e850aa20b62598df188
font_01_sfnt_off000140c2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x140C2 11404 bytes
SHA-256: 89cfc0dc55215756dff82dea75129220ec5c7f9e7f52a6c718151a46b74df146