Malicious PDF — malware analysis report

Static analysis result for SHA-256 ad0f8da17b328da7…

MALICIOUS

PDF

83.1 KB Created: 2021-05-28 11:52:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: 02c8c8674ec3a2f811496d896f566639 SHA-1: 46ced01dcb5183d9947762a724b85e566b50cbc7 SHA-256: ad0f8da17b328da7509739dfc39269a64c747a66f77ff6ca9a79eecc840ec5e0
244 Risk Score

Malware Insights

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

The sample is identified as malicious by multiple heuristics and a machine learning classifier, specifically flagging it as a PDF phishing trojan. It functions as a link farm, containing numerous embedded URLs that lead to external sites, with at least one identified as a malicious redirector. The document body is heavily obfuscated, preventing a clear understanding of its intended lure, but the overall structure and URL distribution strongly suggest a phishing or malicious redirection attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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
  • 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/strik?utm_term=cuantos+litros+tiene+un+tonel+de+agua In PDF document text
    • https://static.s123-cdn-static.com/uploads/4389127/normal_5fcc49012c7a0.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4472481/normal_604f74b118d40.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4476427/normal_5fe569889e773.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4462066/normal_60450af99018f.pdfIn PDF document text
    • https://wuguxobexo.weebly.com/uploads/1/3/0/7/130739488/2879efd.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4373004/normal_5ff261ca75527.pdfIn PDF document text
    • https://kazajibabagak.weebly.com/uploads/1/3/4/4/134467412/4532938.pdfIn PDF document text
    • https://gusemotasejodab.weebly.com/uploads/1/3/2/7/132741535/6990205.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4387035/normal_5ff595708c784.pdfIn PDF document text
    • https://gisetokitalakak.weebly.com/uploads/1/3/4/6/134600310/sidirejunar_sinogul_tutesetegodir.pdfIn PDF document text
    • https://debozapo.weebly.com/uploads/1/3/1/1/131164198/nuzabovik-vesad.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4449629/normal_604acfcfc98e3.pdfIn PDF document text
    • https://pamokevavazodo.weebly.com/uploads/1/3/4/3/134386981/kabakofozob.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4409627/normal_6038683b9c7c3.pdfIn PDF document text
    • https://paniwotipetusu.weebly.com/uploads/1/3/4/6/134614288/jisetoviberutex.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4502236/normal_6011537021acb.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4477147/normal_5fd1f47c91345.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/4219f5c7-0b38-4147-84cc-aad7fa95318e/volume_of_cubes_and_cuboids_powerpoint_tes.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5950fb4a-2ef6-413b-be09-3252227e184c/road_to_kingdom_manga_wiki.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c99cda27-7ea9-4dfa-8f0e-3830baede2eb/casio_aqs810w-1avcf_solar_sport_watch.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e426e902-6d61-463a-a504-ed2158abf92a/suxositer.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/65752a5a-87fe-46ff-b195-0793486e186d/the_heart_of_yoga.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_off000102ea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102EA 4896 bytes
SHA-256: dfe7b08837ccad6c05e790782c32568fad8714f6bd5a377185f1629b9c8fc8a9
font_01_sfnt_off00011398.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11398 13044 bytes
SHA-256: 8f3e73d3ce46365ae2455c0e59cbbde84c607602df1fd30e8e62e008f3de33b6