Malicious PDF — malware analysis report

Static analysis result for SHA-256 bcb51af3e9f1dd2a…

MALICIOUS

PDF

100.1 KB Created: 2021-04-02 08:26:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: c5e2eed079bd412323f70363e8cae049 SHA-1: c4ece5081f69445f2ed07773fbb7d275db16ed5c SHA-256: bcb51af3e9f1dd2a5c1a53a5aec1a0a48953eb62761ce2147bf79f7c04e7eea1
186 Risk Score

Malware Insights

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

This PDF document contains a large number of external links, many pointing to disposable domains, indicating a link farm or SEO manipulation tactic. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or distributing further malware. While no scripts were explicitly extracted, the PDF structure and numerous external URIs are indicative of techniques used to redirect users to malicious sites.

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
  • 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.
  • 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/award?keyword=geographical+coordinates+and+its+characteristics+pdf PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4499319/normal_6018f9318dd53.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4471723/normal_601b5cedaee38.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4414691/normal_602f5d093db85.pdfIn PDF document text
    • http://vizoxusajozigu.iblogger.org/hernia_discal_lumbar_tratamiento_fisioterapia.pdfIn PDF document text
    • https://dijuwinepogiw.weebly.com/uploads/1/3/0/7/130738679/rebif-nudefo-zugosaxataz.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4383698/normal_600c45a48cb68.pdfIn PDF document text
    • http://fexekozupupuge.22web.org/oedometer_test_lab_report.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4480148/normal_5fde35931e4c6.pdfIn PDF document text
    • http://tokio-2020.fun/wosomop93f81.pdfIn PDF document text
    • http://badgesverified.com/basic_security_testing_with_kali_linux_1xc7cx.pdfIn PDF document text
    • https://terunutu.weebly.com/uploads/1/3/5/3/135319236/0b002.pdfIn PDF document text
    • http://predouche.xyz/civil_service_exams_nyc_study_guideapcxy.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://neropalumej.rf.gd/6509909307.pdfIn PDF document text
    • https://09235f31-469a-4613-94fc-36d04c1f642a.filesusr.com/ugd/8b6407_7fbe92e6d06c44ec9076763d8031abab.pdf?index=trueIn PDF document text
    • http://xaramoturowuf.rf.gd/devinod.pdfIn PDF document text
    • https://de2ee6d5-caaa-4265-b15c-40100ab77d99.filesusr.com/ugd/d43733_44f85dd2d4014239b33d1969a2840921.pdf?index=trueIn PDF document text
    • https://68a74d12-89ac-4a94-b826-09ad332a30bf.filesusr.com/ugd/1a0392_58789e57cb6c4eacbf233f1ed3d5b66d.pdf?index=trueIn PDF document text
    • http://gogozibopuxut.epizy.com/george_foreman_grill_cooking_steaks.pdfIn PDF document text
    • https://cbb9655c-b60d-4095-8c1c-bb5f9a2903c5.filesusr.com/ugd/4dd980_b3c307bd64354763aec1ca43f96e22ee.pdf?index=trueIn PDF document text
    • https://521a9f5b-5c7e-4f25-a9e4-5446fb1b1975.filesusr.com/ugd/c1a494_271aaa14415a43b9bef14c8db5f6ff31.pdf?index=trueIn PDF document text
    • https://09235f31-469a-4613-94fc-36d04c1f642a.filesusr.com/ugd/8b6407_22c6499cf776458283c3cbadbed14dc0.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
    • 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_off00012f72.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12F72 5448 bytes
SHA-256: 048789b8f8dcef73869a947db3175e07ee0ceb88b13948cb335206e2d4fe05cc
font_01_sfnt_off000141fa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x141FA 13092 bytes
SHA-256: 6bdd557c842949c711349b9184db71db45aba06321850355c852542f43547814
font_02_sfnt_off00016dc2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16DC2 16036 bytes
SHA-256: 354dce64f07f3d7acdf6a04edf763950ffbfec4edcbb4bfe17b65a83544077bb