Malicious PDF — malware analysis report

Static analysis result for SHA-256 3866fc254f8c11b1…

MALICIOUS

PDF

83.9 KB Created: 2021-04-02 17:19:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-16
MD5: 053a6237606d0483dbfe3372e7b26615 SHA-1: df5a402e6fffc18e2e75527030249352b4def9c8 SHA-256: 3866fc254f8c11b12de6ce07ca420800752a02ae24af715396875170946f34af
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many pointing to disposable domains, indicating a link farm or phishing attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of a phishing or malicious redirection scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9989

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://xajibur.ru/award?keyword=administra%25C3%25A7%25C3%25A3o+da+produ%25C3%25A7%25C3%25A3o+chiavenato+pdf PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4387819/normal_6026ac71a3674.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4448124/normal_5fd0ac40268b7.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4413693/normal_603ec01edcac7.pdfIn PDF document text
    • http://tometifo.getenjoyment.net/42112535816.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4373304/normal_5ff2d84ac078e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366308/normal_6058af2511fd7.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4415782/normal_603880f6ade8b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4422144/normal_60340493559e0.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4497395/normal_6060eb6a28299.pdfIn PDF document text
    • http://vorakumezaxof.mygamesonline.org/nouns_verbs_adjectives_adverbs_worksheet.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4370071/normal_6000320a011fe.pdfIn PDF document text
    • http://rixujewo.getenjoyment.net/63346441530.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/17b8da5b-cb53-4bb8-a8b8-6bd712dcaaf9/armor_of_god_bible_study.pdfIn PDF document text
    • http://ligekasuxube.onlinewebshop.net/basic_algebra_word_problems_worksheet.pdfIn PDF document text
    • https://s3.amazonaws.com/wefadep/google_play_store_apk_5._1._1.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f7c26594-aeb0-4c9d-9f37-58484a4b0106/where_is_the_flame_sensor_on_my_york_furnace.pdfIn PDF document text
    • https://s3.amazonaws.com/tesodagiwor/baby_doll_images_for_whatsapp_dp.pdfIn PDF document text
    • https://cb38ef3f-1f2c-4622-8962-dca261660167.filesusr.com/ugd/3ae201_1bf7edf08edd434ea11d089923839ff3.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/488c5dfa-49f7-4524-87bd-e29913b17447/42713321125.pdfIn PDF document text
    • https://e028ba52-6c86-493e-86b7-fecf7cd1c3eb.filesusr.com/ugd/bcb9fd_befb1cc2533e453f9b4b0c2c00bd8410.pdf?index=trueIn PDF document text
    • https://443275ec-395d-4f86-84c9-2ed7a250e117.filesusr.com/ugd/7d471d_c7467c87d15047d892541f5ba89de9e3.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/ff08a731-d382-4fdc-8f4b-88f2fcc11fd6/28135444980.pdfIn PDF document text
    • https://46fb9a51-9e16-4ad8-811e-2f7ed01702f7.filesusr.com/ugd/53363c_c71bd2ae9c9b414f972fee96134105f8.pdf?index=trueIn PDF document text
    • http://biwosagamivi.myartsonline.com/91987425364.pdfIn PDF document text
    • https://0df22b04-17ae-4e65-9af8-3af4445b4601.filesusr.com/ugd/71fd01_d211591381b1458a874458536aec9e51.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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ef0d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF0D 5912 bytes
SHA-256: 8a69d85961230aed801e12909be4677af902f090ed79dff0c9303dce24afa24a
font_01_sfnt_off0001022c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1022C 13320 bytes
SHA-256: 53cefbe5ecc340cf96d5b478f678ff2998c567cb33b6537e250ee1973604ac1b
font_02_sfnt_off00012a25.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12A25 16204 bytes
SHA-256: 532315dfdc59b350d447ad91845dd8cc72a836e684f536ab9a4305dc5b53fb8e