Malicious PDF — malware analysis report

Static analysis result for SHA-256 991c014b44f0ab60…

MALICIOUS

PDF

92.3 KB Created: 2021-05-30 22:35:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-23
MD5: be4606b60aa04001272fe1dd378bdf1f SHA-1: 264d1c79465b9805733538d347f7160787fe7482 SHA-256: 991c014b44f0ab60d98cdba7128381f0dae62310c69aa6f49b4e5a3e164bfd47
244 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF document exhibits characteristics of a link farm, containing a high volume of external links pointing to various hosting services, including disposable ones. One critical heuristic identified a link to known malicious redirector infrastructure. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution through these links.

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
  • 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://dafemum.ru/strik?utm_term=cyberpunk+campaign+ideas In PDF document text
    • https://wivezinafixozut.weebly.com/uploads/1/3/0/9/130969190/4397ce5dfa07ad.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4491450/normal_5fd9f41cc4656.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4380382/normal_6058094df2057.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4389571/normal_601a7147a2282.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4490123/normal_601bb15306c2b.pdfIn PDF document text
    • https://punopisa.weebly.com/uploads/1/3/7/5/137516802/magusamipev_xedupokikufa.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4472198/normal_600252ee5d330.pdfIn PDF document text
    • https://damenuxorofupob.weebly.com/uploads/1/3/4/7/134711178/146326.pdfIn PDF document text
    • https://dolopexoje.weebly.com/uploads/1/3/1/8/131872138/0eb5439192a.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4453909/normal_5fe2af10e414a.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4408177/normal_5fd7ebae71bed.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4408598/normal_603dec9837607.pdfIn PDF document text
    • https://vevumugenewasu.weebly.com/uploads/1/3/0/7/130776279/9fdf289.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4496170/normal_606b9fd4486aa.pdfIn PDF document text
    • https://sagojuxejuzogug.weebly.com/uploads/1/3/4/5/134598596/101f11.pdfIn PDF document text
    • https://daginunus.weebly.com/uploads/1/3/4/5/134597638/c16853.pdfIn PDF document text
    • https://puvebimu.weebly.com/uploads/1/3/4/3/134311544/4b5ec66b9257f.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4420245/normal_5fc83ba188dda.pdfIn PDF document text
    • https://falobulavogibe.weebly.com/uploads/1/3/4/6/134662271/fepulexijuj.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/ab40e56f-1b29-441a-a639-b3012caff4c0/can_you_be_anonymous_on_kik.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d5e4e0eb-ef9d-46c3-bb14-7b0e6d6b1470/67349487720.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/acd271e7-6523-4eab-8767-6d72494b318c/armitron_all_sport_watch_band_replacement.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_off00012a52.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12A52 5572 bytes
SHA-256: 21308164cb2236e9a44a5b9382b553f05b647cc0bbcd69099acb6b9e3b957c53
font_01_sfnt_off00013d30.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13D30 11396 bytes
SHA-256: e0e56efa69d1ede8188f80a620ebef239c59e2f486b90e09a6a2965108114074