Malicious PDF — malware analysis report

Static analysis result for SHA-256 c98d3f1eb4e4b135…

MALICIOUS

PDF

105.3 KB Created: 2021-03-29 05:57:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 371310a9c3a425f2186cb92feb17b481 SHA-1: 8c8bd3d1f4b63a2f3acb37c439bf69cef166eb2c SHA-256: c98d3f1eb4e4b135ee59e625561f2c1b0a9eeb4d0da92b8a5f2cbe435bc6475f
156 Risk Score

Malware Insights

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

The PDF contains numerous external links, with one pointing to 'nipisod.ru', suggesting a link farm or phishing attempt. ClamAV and ML classifiers also flagged this PDF as malicious, specifically as a phishing trojan. The document body, though heavily obfuscated, appears to be related to 'Apnea del sueño diagnostico pdf', a lure to entice users to click on the malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 5

  • 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.
  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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/award?keyword=apnea+del+sue%25C3%25B1o+diagnostico+pdf
    • http://uscovidcharts.com/intro_to_algebra_worksheetsbh6ve.pdf
    • http://cancandance.org/glaciers_ielts_reading_answerss0apu.pdf
    • https://cdn.sqhk.co/togixulala/NL1ghif/mimerusuvunibagew.pdf
    • http://dietnatur.fun/employment_confirmation_letter_sample6enzj.pdf
    • https://cdn.sqhk.co/puzusagilem/hjjTgi2/platform_1094_tripadvisor.pdf
    • https://rumodabumuxe.weebly.com/uploads/1/3/1/8/131857513/7be9e920d5a1b.pdf
    • http://ilook.market/xuremewizuzuch5t4.pdf
    • http://cetapp.xyz/darexodolurobunamonafume6wqs.pdf
    • https://cdn.sqhk.co/disonixures/bddugdd/kurarusoxawoxo.pdf
    • https://static.s123-cdn-static.com/uploads/4417662/normal_5fcaedcf481b4.pdf
    • https://cdn.sqhk.co/xonipavu/gKUhajb/62177224681.pdf
    • https://cdn-cms.f-static.net/uploads/4406208/normal_604a9f23a4ad6.pdf
    • https://bufuxilanu.weebly.com/uploads/1/3/4/4/134402831/278477.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/faf52873-b9e0-4bb0-9a2c-fd1abc68d77b/paradise_lost_modern_english_book_6.pdf
    • https://s3.amazonaws.com/sifawekujiki/zikudivovaxises.pdf
    • https://uploads.strikinglycdn.com/files/31925dc6-5654-4735-ad80-cf49f684acb9/miwajijibutite.pdf
    • https://s3.amazonaws.com/xabalaru/barrows_mage_guide_osrs.pdf
    • https://uploads.strikinglycdn.com/files/3877eed4-bfdd-4a7c-b9a6-6ee4f364c1b0/21098349061.pdf
    • https://uploads.strikinglycdn.com/files/33788606-581e-44d9-9e34-21a863caa799/husky_pressure_washer_1800_psi_parts.pdf
    • https://s3.amazonaws.com/napoledunadigo/27532293198.pdf
    • https://uploads.strikinglycdn.com/files/efb2e8d8-0544-4181-88f7-d03c04d2754b/xuzuvesotamulubexaju.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • https://medlineplus.gov/spanish/sleepapnea.html
    • 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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00015da8.bin
94cc0675cc0ecac1fa7656a7a780ea2b1080e45dbae7e00a61f4fcc69867e81a		 pdf-font-stream PDF embedded font (sfnt) at offset 0x15DA8 5428 bytes
font_01_sfnt_off00016ffa.bin
222267cbb736d1bc73b83af7c01db218704ed14b2d4dd5f068935318d07c45f1		 pdf-font-stream PDF embedded font (sfnt) at offset 0x16FFA 11480 bytes

Open this report in the interactive analyzer, or submit your own file for analysis.