Malicious PDF — malware analysis report

Static analysis result for SHA-256 5a20205f4f307b0c…

MALICIOUS

PDF

82.8 KB Created: 2021-06-06 08:22:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-13
MD5: a55bf8284bd648e9c5ad21051f7f8be6 SHA-1: 80742c0754cee986c4bab156f5e1918ccfb3f989 SHA-256: 5a20205f4f307b0c0eff4112cb5c472a092f21bbf642b959cbef7d7beef819c8
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 hosting, indicating a link farm or SEO spam campaign. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or distributing further malware. No scripts were extracted, but the embedded URLs are the primary indicators of malicious activity.

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
  • 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://chcial.ru/pbw?utm_term=lettre+de+motivation+pour+un+poste+d%2527enseignant+chercheur PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4385235/normal_5ffb98980ef36.pdfIn PDF document text
    • https://voloxamofe.weebly.com/uploads/1/3/0/8/130874475/wenumemeposugix.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4368474/normal_602e70c6a26b2.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4476567/normal_603022f14bd14.pdfIn PDF document text
    • https://lenatazuponos.weebly.com/uploads/1/3/4/8/134888684/pedafuzebaj.pdfIn PDF document text
    • https://zuvaxufar.weebly.com/uploads/1/3/5/9/135993026/1740181.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4497695/normal_60295f8b49bca.pdfIn PDF document text
    • https://guvikaki.weebly.com/uploads/1/3/4/5/134519546/sexolapepipak.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4470028/normal_606b8537b53e4.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4450048/normal_5fe53b06379ef.pdfIn PDF document text
    • https://situzofunuk.weebly.com/uploads/1/3/5/3/135305293/3062311.pdfIn PDF document text
    • https://vipamabukaxeban.weebly.com/uploads/1/3/0/8/130874648/livorafazudek_pideniresur_turivafuzasus_wifexuvetubu.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4459477/normal_5ff8c2ffd8b48.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4379855/normal_603c0213dac4c.pdfIn PDF document text
    • https://jazewaxuk.weebly.com/uploads/1/3/4/3/134357124/wesolegu.pdfIn PDF document text
    • https://vizefibamoraxob.weebly.com/uploads/1/3/4/6/134613498/2152811.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://uploads.strikinglycdn.com/files/19f13cbc-6bf9-4601-a7a4-6270f3d39c8f/lenezi.pdfIn PDF document text
    • http://tazijebep.pbworks.com/w/file/fetch/144427551/neniluj.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/414982f3-6dd2-48a6-9bbc-7dd8a09ccdef/phonak_brio_3_r-c_reviews.pdfIn PDF document text
    • http://wiwedano.pbworks.com/w/file/fetch/144589812/what_are_the_top_10_most_sold_books_of_all_time.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/162a55cd-7c5d-44ff-9b62-590ac6456683/fonelewiserirelumufipibis.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f538.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF538 5372 bytes
SHA-256: 681bdaa98e465d08066f1dd360eb99d5233c6a507baf8707c106254726c8eecc
font_01_sfnt_off00010759.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10759 11924 bytes
SHA-256: ce593fa7356f617f8d0760f98de126af0fbfb808947d51075ddfd599f4eab4d1
font_02_sfnt_off00012cb1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12CB1 4324 bytes
SHA-256: cd94ef65598b1866d0653cdd88243d989fd81359c0e770c2d3a4858f1c2f6d34