Malicious PDF — malware analysis report

Static analysis result for SHA-256 dcf2512388596f52…

MALICIOUS

PDF

78.5 KB Created: 2021-04-19 03:44:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-18
MD5: f456bfed5ce95741e38b86e5f42934be SHA-1: 91f8c297cc84a43c29c5421a204400608222dba6 SHA-256: dcf2512388596f52566afaa66bdeec638193aac5a8bcf73396268dc0e2c257e8
186 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. 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 0.9994

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/strik?utm_term=how+to+control+tv+sound+with+firestick+remote PDF link annotation
    • https://cdn.sqhk.co/kolokejo/oqihjdv/gitabiwi.pdfIn PDF document text
    • http://grinallex.shop/19013261393vxpb6.pdfIn PDF document text
    • http://cyberlife.store/tawijemego5hsa.pdfIn PDF document text
    • https://cdn.sqhk.co/teforoke/hghmigV/gepiwibovonelamutow.pdfIn PDF document text
    • https://cdn.sqhk.co/vawapisoxe/sacYGja/blue_bot_class_bundle.pdfIn PDF document text
    • http://show-visitor.xyz/77386006126wvqo2.pdfIn PDF document text
    • https://cdn.sqhk.co/fezavomol/1jgghpa/96456883793.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://8acf0fc4-2da8-4686-9788-d7840b5449fc.filesusr.com/ugd/fab691_949312a0e2c14e90a3583a5b427d0587.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/wajufifenoxuj/lord_of_the_flies_1963_full_movie_review.pdfIn PDF document text
    • https://s3.amazonaws.com/zozuxukoxo/how_to_remove_jacuzzi_tub_jets.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2595c171-65fb-4666-9d9c-76720408262c/bosch_tronic_3000_us7_electric_point-of-use_tankless_water_heater.pdfIn PDF document text
    • https://4adff18d-dc39-4349-be2c-eeb12737f1cb.filesusr.com/ugd/9117e0_8b3adc1f1f8f4a8a9fc52005b0c94044.pdf?index=trueIn PDF document text
    • https://e62d90d9-845b-491d-b9b1-804d55ccd6e6.filesusr.com/ugd/6af1ed_75acdbb17cce487890e0e157a64d9e0d.pdf?index=trueIn PDF document text
    • https://58552d80-c20c-4e4f-99b9-91bedbcc07a3.filesusr.com/ugd/c18496_01bb742dad0148b2ae3f87f0bc5a37f3.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/8309dc33-635d-4924-a7d7-11db6d4ac7c2/37435235753.pdfIn PDF document text
    • https://55d63786-14d6-44de-84d0-33f1fb383c44.filesusr.com/ugd/45fd81_39e3fec9b9e14cbd91f58d9c3a24d49b.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/wupixufekijax/8752163380.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/609e4bdc-3da3-4836-8add-11f5d0044a33/how_to_root_samsung_sm-t230.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c1ffc921-2261-4995-8050-038ce55262d9/amc_8_2020_scores.pdfIn PDF document text
    • https://da18e6a8-d720-42de-a88c-3f13daad7efb.filesusr.com/ugd/08fe48_8f04e26acb0145f389e63d90213ee529.pdf?index=trueIn PDF document text
    • https://5e024257-ca51-40df-b6b5-a3104c7b7124.filesusr.com/ugd/97368a_06419b7db8854c369398f8b6ec4a9a15.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/f181fe0d-950c-48d0-b114-d6eb17c37b0a/modos_de_produccion_segun_el_marxismo.pdfIn PDF document text
    • https://11ab4cf5-156d-4417-99e9-5039b2a7eb5f.filesusr.com/ugd/82d61e_015229e71c264389b08aa94cc236ac54.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_off0000f23c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF23C 5228 bytes
SHA-256: c4ea5b009749edcb628de3643abbf4449b1b4eef45c9e379c65bfb26d1f72fd6
font_01_sfnt_off000103f3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103F3 11824 bytes
SHA-256: c5f91473a30b4bc2dfd166e94bc5701623896bac74451db1b0e83ad815dbc914