Malicious PDF — malware analysis report

Static analysis result for SHA-256 d3c4ef528b1ed88d…

MALICIOUS

PDF

82.1 KB Created: 2021-03-22 10:31:17 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 1e49689a572ddcb2e679cabedbd9e9ed SHA-1: af7cd38a5edf7f95e54fd4d2fc6434b859d1c398 SHA-256: d3c4ef528b1ed88d926f64805cab3dcf5ce6faff5b22d349b9947a28d776a1a4
156 Risk Score

Malware Insights

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

The sample is a PDF file flagged as malicious by ClamAV and an ML classifier. It contains a large number of embedded external links, with a critical heuristic identifying it as a 'PDF_SEO_LINK_FARM'. One of the primary malicious URLs identified is https://crophysi.ru/123?utm_term=formed+from+basalt+columns, and another suspicious URL is https://vebavorosufate.weebly.com/uploads/1/3/4/7/134742301/nivebomi.pdf. The document body is heavily obfuscated and unreadable, but the presence of numerous links suggests a phishing or link-farming attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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://crophysi.ru/123?utm_term=formed+from+basalt+columns
    • https://vebavorosufate.weebly.com/uploads/1/3/4/7/134742301/nivebomi.pdf
    • https://cdn-cms.f-static.net/uploads/4414335/normal_603909b132d2a.pdf
    • https://static.s123-cdn-static.com/uploads/4378856/normal_6006e6ff43061.pdf
    • https://xuzajigafekaba.weebly.com/uploads/1/3/4/5/134584338/nemavibadeso.pdf
    • https://bozuwamit.weebly.com/uploads/1/3/4/5/134527300/9319043.pdf
    • https://cdn-cms.f-static.net/uploads/4392871/normal_6035657926cbc.pdf
    • https://wadaletabuj.weebly.com/uploads/1/3/2/6/132695896/nitesupunez_jekom_depos_salug.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://www.daltonmaag.com/
    • https://s3.amazonaws.com/sejakopa/merrills_principles_of_instruction_ppt.pdf
    • https://2703069b-a6ff-4ff9-983c-db139a8d76ba.filesusr.com/ugd/8b61cf_8f2b6ff0387347518e8e291476adcccf.pdf?index=true
    • https://s3.amazonaws.com/jolituzoji/expense_report.pdf
    • https://c3373aeb-ed74-4f2d-b631-fa679e0a3f6f.filesusr.com/ugd/cbe7f7_ba27a8f10fe5481e97f63b12e67a7119.pdf?index=true
    • https://uploads.strikinglycdn.com/files/c2705445-abc6-43b9-a664-41727feba426/is_kenmore_sewing_machine_385_low_shank.pdf
    • https://s3.amazonaws.com/dojivewobasuval/nvidia_jetson_nano_datasheet.pdf
    • https://aaf8962b-2ea5-4403-bfea-7c32f2b3f77e.filesusr.com/ugd/8f3a65_1a6cabbe84ff402f9a31c2b74f1fd5d3.pdf?index=true
    • https://uploads.strikinglycdn.com/files/13f9b0fc-f158-43e8-956d-b98096cc0e9c/51080816162.pdf
    • https://bf6af823-cb0d-4ee8-9d5b-4f0b1de5ed24.filesusr.com/ugd/9eb187_f7c784d7d40b40a080d015cc84ef01d4.pdf?index=true
    • https://uploads.strikinglycdn.com/files/4f2111d8-2dbd-48b1-b3ff-fe45b9a73291/95260612418.pdf
    • https://944456f3-75eb-4cd6-bbfd-656b3713ada1.filesusr.com/ugd/2c8d66_a16905ea8f12419194e9c15319c3add0.pdf?index=true
    • https://uploads.strikinglycdn.com/files/ac5f7b91-0d99-4070-843a-9c474c3c2870/murder_on_the_orient_express_book_review_new_york_times.pdf
    • https://uploads.strikinglycdn.com/files/ce8b1635-4712-4c3f-ae37-1e62eba42cbf/himno_nacional_mexicano_en_nahuatl_letra_completo_y_en_espaol.pdf
    • https://uploads.strikinglycdn.com/files/c6e64488-95f8-4bd0-80e7-3b4275878293/vw_polo_6r_service_schedule.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f3f0.bin
4c1e9147c68aac71de1af91cd1e12818d02207015d8baed09cc640a890af14f3		 pdf-font-stream PDF embedded font (sfnt) at offset 0xF3F0 5096 bytes
font_01_sfnt_off00010526.bin
5e0b985223ab2ac4672b6b51222282e9df1c49eed0c9a93c35422dc4df05dec7		 pdf-font-stream PDF embedded font (sfnt) at offset 0x10526 12296 bytes
font_02_sfnt_off00012cc7.bin
b50a2106bf82917db0cd3cf88f63c5e8cc3298b343ace5cffc591b35df33d24c		 pdf-font-stream PDF embedded font (sfnt) at offset 0x12CC7 4324 bytes

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