Malicious PDF — malware analysis report

Static analysis result for SHA-256 81fdd1dde709b58a…

MALICIOUS

PDF

79.7 KB Created: 2021-03-29 15:48:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-24
MD5: b2caa800166a93dd821e0ded11d9311c SHA-1: a86771cf1b15c16545c462c72b8cc5544bf07aa1 SHA-256: 81fdd1dde709b58af8c88313740389fb9003b7b1ccc187c562c2cb773aa19201
244 Risk Score

Malware Insights

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

The PDF contains numerous embedded links, with at least one pointing to a known malicious redirector. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or distributing further malware. The presence of embedded URLs and the PDF structure suggest an attempt to trick users into visiting 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
  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • 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://crophysi.ru/award?keyword=exercicios+de+alcoois+pdf In PDF document text
    • http://natasisenexu.22web.org/68101775261.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://f815f12b-539f-4060-8ed9-abd2caada31b.filesusr.com/ugd/ceb2e8_e147e0c82e5c47f4bdca4aff1940a2ee.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/714e2ac0-20de-4186-9cf5-6bc43195c7c0/service_schedule_vw_tiguan_2018.pdfIn PDF document text
    • https://8eccd3b7-fb20-4588-a5b5-4d8c58591879.filesusr.com/ugd/0e6328_33c18f7637b5452bb837a94c5881688d.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/9e3a607e-6b86-47f1-99b0-a4222f6e4775/90890758854.pdfIn PDF document text
    • https://4b002d3c-a55f-42ce-816c-238f848e88a9.filesusr.com/ugd/3398cc_9e71c2bf02fd4c29b38fb78c25677aec.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/443b8183-170c-4707-9e1c-4f49b2cfbaa5/95578259252.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c2f9dd22-1003-4a9d-a5ee-98acc04e327c/lalirajurinavux.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b1c8e39e-75b3-4953-a01f-87bbc99c4078/wutevivajusokewafav.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2188cce0-eff6-4d0b-ad12-c9e6bcd30e7b/72605242674.pdfIn PDF document text
    • https://631ffb88-cf2d-4844-8d6b-9338a1b21cc5.filesusr.com/ugd/d24e6f_cd4c1b37fcd44391a9bcf4e7b3b61770.pdf?index=trueIn PDF document text
    • https://22449060-8e30-4723-8828-967625cce342.filesusr.com/ugd/eddc50_c77b1b1b84d04a408f4c1a84f94d8a7f.pdf?index=trueIn PDF document text
    • http://maxefaronuxugur.epizy.com/narrative_perspective_analysis.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8296e79a-5f5a-4e7b-a85c-4e7be4f32c74/jisuboposobag.pdfIn PDF document text
    • http://luruloligof.rf.gd/angry_birds_games_free_for_mobile.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e7ec764e-6c35-4645-8161-08fb5142db5d/26979499593.pdfIn PDF document text
    • https://ddd59a73-be73-4575-bd7b-2e5900175f8b.filesusr.com/ugd/5dc0ef_93069fee7a0b403cab8eb00c8f0e88f2.pdf?index=trueIn PDF document text
    • https://dec4a425-646e-450a-80ca-a73a75d058ad.filesusr.com/ugd/ba3095_ef6b98a7e0484e5688f7ee90404e0821.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/e8fb75ee-f907-4a53-bd89-17947368298b/is_a_new_twilight_movie_coming_out_2020.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/20d0bcbb-ff3a-4f2f-b68f-17495254bb19/sanatireduvebafobut.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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000df22.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF22 4776 bytes
SHA-256: 6fb4018276fc2bcace315d9a6215bd3664a0e5b622bf50ddbedc3567440a4bc8
font_01_sfnt_off0000ef62.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF62 2520 bytes
SHA-256: 26ac93315814f42a2399db89c53c757e72434be049311e25573298e7905510f0
font_02_sfnt_off0000f9b9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9B9 12988 bytes
SHA-256: e3b9b609043049d0b813bc463323f5c223d4ceb31ac5554091e0edebccee3794
font_03_sfnt_off0001214b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1214B 4324 bytes
SHA-256: a542ec26cea93e049a2e27cd59b1347dd9bbdea13775fd7b822b3c2b3136116f