Malicious PDF — malware analysis report

Static analysis result for SHA-256 8dfdd4b12e53d589…

MALICIOUS

PDF

121.9 KB Created: 2021-05-03 14:00:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-18
MD5: a6fdb98aaa0c790558dc86e0d861045a SHA-1: 5c527d324bfd7f9b48ab390db34a106a0a3397bc SHA-256: 8dfdd4b12e53d589d59c803c610332f35cd5c067c7a16a76698075467e8cb2bd
194 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution T1059.007 JavaScript

This PDF document was flagged as malicious by ClamAV and an ML classifier. It uses an urgency-based lure. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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://xezojetit.ru/strik?utm_term=create+json+object+array+c%2523+newtonsoft PDF link annotation
    • https://cdn.sqhk.co/doginifa/e9BjjYI/fitbit_versa_3_review.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4406455/normal_604d4741634e6.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4375357/normal_5fdee57d2f266.pdfIn PDF document text
    • https://cdn.sqhk.co/linidivez/aheZPhh/bad_banks_cast_staffel_1.pdfIn PDF document text
    • https://cdn.sqhk.co/zunezafi/hdPTcge/81109938091.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4460071/normal_606b95589835d.pdfIn PDF document text
    • https://begosibaluta.weebly.com/uploads/1/3/0/7/130775163/520bf42d5c6e38.pdfIn PDF document text
    • https://cdn.sqhk.co/titukopano/jEU8xsX/40385687095.pdfIn PDF document text
    • https://ponukikoruxa.weebly.com/uploads/1/3/4/3/134343798/3156482.pdfIn PDF document text
    • http://instgrmmverifiedbadge.com/15958704049om2mb.pdfIn PDF document text
    • http://jadebey-x.com/libro_de_fsica_2_de_secundaria_editorial_castillo_contestado797lo.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://uploads.strikinglycdn.com/files/1e3801a5-2eeb-41b8-8de1-53714e78fdf1/stihl_bg_86_carburetor_diagram.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0f717ab2-79f1-40d1-b33d-229886847171/vermont_castings_radiance_gas_stove_manual.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b2dc97b1-31af-4058-95e6-3df1a6f311da/xavurevoxulemabax.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9132a058-5f36-49b1-9b69-c4ea3a932b97/examples_of_banduras_social_learning_theory_in_the_classroom.pdfIn PDF document text
    • https://7fd672c9-0ac8-42d3-9d3c-9ebb2fbea2b4.filesusr.com/ugd/92785a_1a6531b2803f4c3eb002055db032fbe5.pdf?index=trueIn PDF document text
    • https://8ed7b8cb-9bae-4def-ad9b-66b28cd11f91.filesusr.com/ugd/740d8c_bf92d86a73e04245b823c86caaf9c293.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/304629c7-e233-4eb8-926d-eb068b55c487/monububetotufisage.pdfIn PDF document text
    • https://368051e9-4199-40ea-b9a2-dc6e6f83cb3b.filesusr.com/ugd/6260fe_af6c0bf3c84b414f94e5aae5bb6db7ba.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00019247.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x19247 4844 bytes
SHA-256: 6d9555eb7005894e1876929b463d91ae6dfa1ee931c1626f74d7c38b4eb18f00
font_01_sfnt_off0001a2d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1A2D0 11952 bytes
SHA-256: 02acb5632ce6b9a1dc367cde65637acbf455c1423ab6f5b81eaa40e2421a2472
font_02_sfnt_off0001cb9c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1CB9C 4324 bytes
SHA-256: cd94ef65598b1866d0653cdd88243d989fd81359c0e770c2d3a4858f1c2f6d34