Malicious PDF — malware analysis report

Static analysis result for SHA-256 c6fb55998707dd4f…

MALICIOUS

PDF

74.5 KB Created: 2021-03-07 06:21:49 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-25
MD5: 1447944b7e09427f8a73ca93aa823a36 SHA-1: e07849a60254efa724ee8051e6ccbf26dc88dd3f SHA-256: c6fb55998707dd4fe76f51027c117057830bd82df733d42f8b28847955055f55
186 Risk Score

Malware Insights

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

This PDF document was identified as malicious by ML classifiers and ClamAV, flagging it as a phishing trojan. It contains a large number of external links, many hosted on disposable domains, suggesting a link farm or SEO spam operation. The document body, though heavily obfuscated, contains references to 'elastic potential energy problems worksheet', indicating a lure to disguise the malicious intent. No scripts were extracted, but the PDF structure and numerous external links point towards a phishing or malicious redirection scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9988

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://nipisod.ru/wix?keyword=elastic+potential+energy+problems+worksheet PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4486190/normal_60018f25e44d0.pdfIn PDF document text
    • https://libadelalisam.weebly.com/uploads/1/3/4/5/134579317/2dfdded5c1e.pdfIn PDF document text
    • https://wivupenoremew.weebly.com/uploads/1/3/0/7/130775018/wirikujopexel-podumu.pdfIn PDF document text
    • https://cdn.sqhk.co/zapiseniw/UjglAjf/bakasub.pdfIn PDF document text
    • https://cdn.sqhk.co/xanovika/Q0EfSha/galejinezafinufemijo.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4475863/normal_6024a3abe6b71.pdfIn PDF document text
    • https://fiwinibikevuli.weebly.com/uploads/1/3/5/3/135339450/rodazomazifimo-zubirukub-xokebomipuva.pdfIn PDF document text
    • https://biziremidawa.weebly.com/uploads/1/3/5/3/135397591/531744497ee15.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4473053/normal_5fd26d1783b3f.pdfIn PDF document text
    • https://cdn.sqhk.co/dixufeja/gg8Clha/37060549629.pdfIn PDF document text
    • https://cdn.sqhk.co/xawodoze/i8jrCgf/91291791732.pdfIn PDF document text
    • http://fontawesome.iohttp://fontawesome.io/license/In PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/sojebelevenex/data_structures_and_algorithms_using_c_free_download.pdfIn PDF document text
    • https://05491ccc-77c7-428b-9c25-74f2c6c50d4a.filesusr.com/ugd/d51d36_db621949b7114695ac29b34788e6adc1.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/7de52610-cc57-451d-8a28-9fea5397d3c8/five_nights_at_freddys_4_free_download_pc.pdfIn PDF document text
    • https://s3.amazonaws.com/lakadutof/88959667477.pdfIn PDF document text
    • https://926da24b-d3df-4aea-ac1b-ebdf7359a9e7.filesusr.com/ugd/fef925_96fce63d48664b6d8b1a97d079352841.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/64cd40b8-24fb-40f3-af0b-927e5abba97b/69187876928.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/35b24ceb-cf8e-42c7-9f3b-c8045e68613b/ruxorimurumifuvokasewax.pdfIn PDF document text
    • https://s3.amazonaws.com/rupatojuko/lexegiwinasa.pdfIn PDF document text
    • https://c2dbac7f-2075-4dc1-ad03-af0d0352bff2.filesusr.com/ugd/278743_eb1758d6b83845df8da0049b69292ba6.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/0a3feee3-a48d-41bf-b772-b882ae94e22b/what_is_the_alpha_prefix_for_anthem_bcbs.pdfIn PDF document text
    • https://dda5c79a-a75d-44d9-a006-48dec3bfe172.filesusr.com/ugd/115d6e_6984cc9f93804af0b7a433ee94f52abd.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/foneniz/70520524673.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/466a4aec-4aaf-474b-88ce-d0fbd3974c2f/26551180018.pdfIn 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_off0000dd53.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD53 1964 bytes
SHA-256: 06d927bb2b6daf891478ab4cab90709232d593f7c9b2cc46f53d704c02e6609f
font_01_sfnt_off0000e6a1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6A1 5700 bytes
SHA-256: aa51a3873e084b7dfde4670dfbd0317aa40a028962c0f12db5bd2f16611a1bb3
font_02_sfnt_off0000f9f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9F6 9980 bytes
SHA-256: e2fe53271a8548c2454da39751321f283bef384614fc8454876837e19407a970