Malicious PDF — malware analysis report

Static analysis result for SHA-256 23b2ab399d07a102…

MALICIOUS

PDF

83.7 KB Created: 2021-03-20 18:12:02 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-15
MD5: 5be99fbab474ee99fe26a39f819d6bb1 SHA-1: be8a61f82192ca5bc98f25eeb84e6843c15e9663 SHA-256: 23b2ab399d07a1021d96cd90473fe954cfb981898edf6e8cb7968e306de06a0c
244 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

This PDF file was identified as malicious by multiple heuristics and an ML classifier, specifically flagging it as a redirector link farm and a potential phishing or trojan delivery mechanism. The document contains numerous embedded URLs, with at least one pointing to known malicious infrastructure. The presence of a link farm suggests an attempt to direct users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

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://yafferge.ru/123?utm_term=increase+60+by+10+answer In PDF document text
    • https://cdn-cms.f-static.net/uploads/4414334/normal_6047d6c87fe21.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4494166/normal_60228dcb606e6.pdfIn PDF document text
    • https://cdn.sqhk.co/luwonowuwig/ebibwif/download_crazy_taxi_3d_java.pdfIn PDF document text
    • https://rofikilidoxomuk.weebly.com/uploads/1/3/4/0/134017179/58e404d.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4447098/normal_5fedd8522d912.pdfIn PDF document text
    • https://cdn.sqhk.co/xerejijasoma/hbVgfLG/23511395910.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4372086/normal_5fd7b76a3e30a.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4448331/normal_6053890b3eac7.pdfIn PDF document text
    • https://bikafosujikus.weebly.com/uploads/1/3/2/8/132815014/tapinutupaviwe-zawudazoluvomu-jobew-sowok.pdfIn PDF document text
    • https://cdn.sqhk.co/xasakeza/gijiYZh/jomegasusal.pdfIn PDF document text
    • https://cdn.sqhk.co/fufigavaki/lceAzFl/fugadov.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4376878/normal_5fd6e118183e8.pdfIn PDF document text
    • https://vipapixamez.weebly.com/uploads/1/3/0/8/130814430/0a3f7.pdfIn PDF document text
    • https://tefojemitadu.weebly.com/uploads/1/3/1/6/131606809/jomevalaki.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4388407/normal_6028fabfb798c.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://s3.amazonaws.com/dowavelaxam/kinokusiribuzu.pdfIn PDF document text
    • https://s3.amazonaws.com/xazarujokemus/83590137604.pdfIn PDF document text
    • https://e9abb47e-19e5-4ec2-9f3c-2aa4e6f2bf0a.filesusr.com/ugd/92be99_c1c8848f07904f87b25b9e873a524990.pdf?index=trueIn PDF document text
    • https://329f26c8-0235-4118-8622-173d264d9cf1.filesusr.com/ugd/221f3a_36c653db2b6342168ce6eac999d84906.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/xezujuxoz/introduction_to_statistical_learning_hastie.pdfIn PDF document text
    • https://s3.amazonaws.com/vawoginele/98047866548.pdfIn PDF document text
    • https://s3.amazonaws.com/tugafebip/senot.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_off0000ffb9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFB9 4928 bytes
SHA-256: f3940d9a9a3cdaf97a0be5e7c1adb1d4c397361cc6477ee136602f5ed74fd0c2
font_01_sfnt_off00011071.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11071 10284 bytes
SHA-256: 5ea1f912a9ddf942433a04031653de904074c77979ce4963f64169866fd06463
font_02_sfnt_off00013361.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13361 4324 bytes
SHA-256: 1158d95dac44631f497756703988ba3645251422e7ff0015d3fca430225e7c3e