Malicious PDF — malware analysis report

Static analysis result for SHA-256 540c798fc5d1439c…

MALICIOUS

PDF

89.3 KB Created: 2021-03-15 09:26:33 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: ee012b2f10834998d8e3b0f2bfab81ac SHA-1: 984107c7f81fb57bbfe41667447987a79895783f SHA-256: 540c798fc5d1439c3ff4388930c8bdd1ead069300ee74de0f61cdb0c197d89c0
96 Risk Score

Malware Insights

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

The PDF file contains numerous external links, identified by the PDF_SEO_LINK_FARM heuristic, pointing to various domains including zajinet.ru and cdn.sqhk.co. The document body, though heavily obfuscated, contains keywords related to search terms, suggesting a deceptive lure. The presence of embedded URLs and the ML classifier's high confidence score indicate malicious intent, likely to redirect users to potentially harmful content or phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 4

  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • 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/wix?keyword=black+friday+2015+gaming+laptop+deals+2019+canada
    • https://cdn.sqhk.co/rifusofuwedi/hbJjahe/principal_mining_engineer_salary_australia.pdf
    • https://cdn-cms.f-static.net/uploads/4367302/normal_5feaf660be0bf.pdf
    • https://wavujosivisero.weebly.com/uploads/1/3/2/7/132740585/856a4a859c9ba0a.pdf
    • https://kamowomol.weebly.com/uploads/1/3/4/3/134371521/pobuzuja.pdf
    • https://cdn.sqhk.co/zadexona/jjhjgcL/voice_changer_mic_for_gaming_android.pdf
    • https://cdn-cms.f-static.net/uploads/4379489/normal_600cc2060c2cc.pdf
    • https://cdn.sqhk.co/joxejetupafi/Ivjhjez/bulleit_bourbon_10_year_old.pdf
    • https://cdn-cms.f-static.net/uploads/4420025/normal_6022bc4d173e6.pdf
    • https://bidijogez.weebly.com/uploads/1/3/5/9/135993355/surenivobarus-purekagavefine-kekutub.pdf
    • https://cdn-cms.f-static.net/uploads/4373755/normal_6023e25849835.pdf
    • https://fusajebotiv.weebly.com/uploads/1/3/4/3/134320253/mibavumisepasel.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://www.daltonmaag.com/
    • https://9e730ba1-499c-413e-9a09-8a81f8121270.filesusr.com/ugd/0a0016_ebac567bf51f4123b7bac862982308c3.pdf?index=true
    • https://67bb8873-ca08-4da4-87c0-60a8072ebff6.filesusr.com/ugd/a838c0_82e64b9d8bc3453d8ec09e7b1a873bd5.pdf?index=true
    • https://s3.amazonaws.com/welanisowari/78664958275.pdf
    • https://uploads.strikinglycdn.com/files/a01642fa-e96c-4bd7-ae86-94d77db5eef4/dunkin_donuts_ham_wake_up_wrap_calories.pdf
    • https://uploads.strikinglycdn.com/files/4e657c5c-1866-445a-80a3-2de6211e8b77/14051737431.pdf
    • https://uploads.strikinglycdn.com/files/266e3e1b-01f8-4351-b66b-e87f99b0a5ef/78686237545.pdf
    • https://s3.amazonaws.com/jajuzasalikirut/rupees_symbol_in_android_textview.pdf
    • https://48e5b1ff-25fb-49a4-826b-3ad3f3a15688.filesusr.com/ugd/0d632a_c1593da564d247458178f7f62aa51567.pdf?index=true
    • https://1b6fbac1-9b66-4609-9151-81f5d4c316f7.filesusr.com/ugd/5e81b9_75298ffe03f043069fa56e878b603ec7.pdf?index=true
    • https://uploads.strikinglycdn.com/files/7befd3d2-8e47-45bb-960d-d84da5758b1d/how_to_find_disposable_income_from_gdp.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_off00010cf6.bin
b9347e534c5c30b745b9397ce10696cb5a01a9db9becbc514d62940648ab38e4
pdf-font-stream PDF embedded font (sfnt) at offset 0x10CF6 6084 bytes
font_01_sfnt_off0001219a.bin
fbf617a93a011a47627f55c839a77d5b658cdfc0d58b746b93ee67b023dffb42
pdf-font-stream PDF embedded font (sfnt) at offset 0x1219A 11156 bytes
font_02_sfnt_off000147d7.bin
05d2457133b820fa77aa358e30e9acfbad3f04c46ced9a37296d9311117db176
pdf-font-stream PDF embedded font (sfnt) at offset 0x147D7 4324 bytes