Malicious PDF — malware analysis report

Static analysis result for SHA-256 88bfc1ec590594cd…

MALICIOUS

PDF

74.0 KB Created: 2021-03-28 07:28:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-23
MD5: b3aebdf05fc2c7ee90eaef42e76bb5f3 SHA-1: f0a1495df1628212da22645e00037ecfb3a431cc SHA-256: 88bfc1ec590594cdf310c71be69c2f8aa535d1b0cf979701e3a34d760f430bd4
244 Risk Score

Malware Insights

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

The PDF contains a critical heuristic firing for linking to known malicious redirector infrastructure, specifically `https://crophysi.ru/123?utm_term=faringitis+bacteriana+tratamiento+pdf`. It also exhibits characteristics of a link farm, with numerous embedded URLs pointing to various PDF documents, some hosted on disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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/123?utm_term=faringitis+bacteriana+tratamiento+pdf In PDF document text
    • http://turosofatilez.iblogger.org/cuisinart_coffee_center_12-cup_coffee_maker_and_single-serve_brewer_instructions.pdfIn PDF document text
    • https://mitafomanamo.weebly.com/uploads/1/3/0/9/130969747/jutugexuwexunozegej.pdfIn PDF document text
    • http://wuwodijutorem.iblogger.org/where_can_i_lookup_sex_offenders.pdfIn PDF document text
    • https://bilugejedegigel.weebly.com/uploads/1/3/4/0/134017605/setijolifemuf_segav_rezesirusim_zisawuxofexitij.pdfIn PDF document text
    • https://bebemabuvi.weebly.com/uploads/1/3/1/4/131453051/32a07e690f.pdfIn PDF document text
    • http://rijupoxog.22web.org/speaking_in_tongues_bible_study.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/26a7860e-94e5-4c55-8bfe-2f311466a3b2/pablo_neruda_books_in_tamil.pdfIn PDF document text
    • https://0298dc5a-7924-4276-8279-06452a5288da.filesusr.com/ugd/b30cf0_f0bbd3e6de174cf98c212f3f0c13111f.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/9ba0d68f-3d3e-4dfa-a065-7eed87a7f9bf/xifepipofutuwewanu.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b7d9ccc8-a913-4b04-9470-ce23964e0f6a/zowuxofa.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/51992087-9b44-4740-8739-224985d84c7e/62553848629.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c2bb0137-fc8a-4003-a9bf-52e5b75e9527/7779992361.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a9094622-c6f7-44f3-b4c3-5f3c5a755b4b/apollo_twin_solo_duo.pdfIn PDF document text
    • https://f16fa5c1-8556-4bba-8f86-04d9c108beb0.filesusr.com/ugd/2c3d75_b908934a7d364fc1a864a7b104616b5a.pdf?index=trueIn PDF document text
    • http://sabaramofedofi.rf.gd/the_secret_life_of_the_american_teenager_season_5_episode_10.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4582d94b-0a7d-441c-b035-4783b25c4ae3/99830249021.pdfIn PDF document text
    • https://c3bb11cb-ba02-405d-8462-2b4421b436e1.filesusr.com/ugd/4c7814_03a3fee16e8443acbb870b02d8e05a8b.pdf?index=trueIn PDF document text
    • http://rujemivegelap.epizy.com/what_is_the_best_app_to_learn_korean_language.pdfIn PDF document text
    • https://2eda13a9-9e0f-47dd-bbfa-a9a5028a3314.filesusr.com/ugd/61c57f_cbc088d8ea644a11a6e355287ba25c56.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/93b734ab-b87e-4b4b-a479-04974e67070e/much_ado_about_nothing_summary_act_1.pdfIn PDF document text
    • http://gexovegamone.rf.gd/choc_septique.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d203d8a7-8a47-4b0f-ad4b-5da1f1780a90/frankenstein_1818_text_vs_1831.pdfIn PDF document text
    • http://sugoxusegisefiz.rf.gd/53514825570.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e1af.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1AF 5540 bytes
SHA-256: f9f76405430992cb0cb57a5880ed6252f3a8234565e5d7e3a37089aad70e4c72
font_01_sfnt_off0000f46d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF46D 10980 bytes
SHA-256: a3024d648a574010e403d5acf94a46dd6c5d51b5816102c0adbb8a8f518ed9c1