Malicious PDF — malware analysis report

Static analysis result for SHA-256 124fa8a28dad5d97…

MALICIOUS

PDF

74.7 KB Created: 2021-03-27 23:04:30 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-10
MD5: 4e893f0546cf0baf28e82bc7aa6c42fb SHA-1: 377b0062fc89482820aadb912767d36662161f7d SHA-256: 124fa8a28dad5d97e651977b195f5e27909fe94c03b47e508c312ef40674392e
124 Risk Score

Malware Insights

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

The PDF contains embedded links pointing to known malicious redirector infrastructure, specifically identified by the 'PDF_MALICIOUS_REDIRECTOR_LINK' heuristic. The document body is heavily obfuscated and appears to be junk data, but the presence of malicious links is a strong indicator of malicious intent. The ML classifier also flagged this PDF with high confidence.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

Heuristics 4

  • 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=large+frozen+hot+chocolate+dunkin+donuts+calories In PDF document text
    • https://cdn-cms.f-static.net/uploads/4403121/normal_6026b84d2ca85.pdfIn PDF document text
    • https://cdn.sqhk.co/vimitewimuwi/cHmicjd/google_chrome_browser_windows_7.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4411922/normal_604af1f762e6f.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4460972/normal_60354fab80cff.pdfIn PDF document text
    • http://balegetiwep.mywebcommunity.org/do_rice_noodles_have_less_calories.pdfIn PDF document text
    • https://cdn.sqhk.co/faserekino/ibmjjJ1/vip_health_care_queens.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4388627/normal_60528718a6724.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366358/normal_603bd42f515df.pdfIn PDF document text
    • http://ninotekega.mygamesonline.org/qaamuuska_af_soomaaliga.pdfIn PDF document text
    • http://fisoxovazesenam.iblogger.org/ages_and_stages_questionnaire_30_months.pdfIn PDF document text
    • http://posadukik.getenjoyment.net/10681371782.pdfIn PDF document text
    • https://cdn.sqhk.co/bomumuxa/jInjjbl/zuforejikidadakawoxu.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4421629/normal_60077d679dd8a.pdfIn PDF document text
    • http://delinapod.mypressonline.com/bsc_magazine_february_2020.pdfIn PDF document text
    • https://cdn.sqhk.co/faroziwe/Vdjjiep/54402842863.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4369783/normal_60012ab478c94.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4380229/normal_601b398249a5a.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4378160/normal_5fc944d15b71a.pdfIn PDF document text
    • http://rigudozefogo.mypressonline.com/north_carolina_drivers_license_office_raleigh_nc.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://4e4301d6-cc9a-4939-960a-6b497c1efea6.filesusr.com/ugd/d78803_58ee511cce7e49a3ac15dd61d98f29bf.pdf?index=trueIn PDF document text
    • http://rosedosoxibi.epizy.com/makefasanunozirezorus.pdfIn PDF document text
    • https://dd67658a-cc17-4e1c-bca5-42bf299a485b.filesusr.com/ugd/07a440_dd55e0f04ff34dfaa6234d1535f7ce1b.pdf?index=trueIn PDF document text
    • https://72a23b54-95c1-47c0-80d6-f7b1310faeb8.filesusr.com/ugd/65b209_0fcd42441dd14c70ba06b1d520b709c1.pdf?index=trueIn PDF document text
    • https://1b15a19f-c8c2-4d9d-8c2f-e97aa7ecfe2c.filesusr.com/ugd/eb6c48_22231a88b2344081abb2213159169731.pdf?index=trueIn PDF document text
    • http://bazogojuzularib.rf.gd/pubenazetezabukixe.pdfIn PDF document text
    • https://662517ce-f374-4037-aebd-99b1dbe00103.filesusr.com/ugd/0c4177_b27c55dc6d0c4885838997263e3d61d0.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_off0000e3a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE3A7 5336 bytes
SHA-256: 04b0f812a37f90db1baec86c5678255ea8c2c8dae9f4d90d6469a7ebd5731b0e
font_01_sfnt_off0000f5d8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5D8 11488 bytes
SHA-256: 464942576a340cf63a122118dacbe980f7ad329c66d0ac708e88db84dd2c436b