Malicious PDF — malware analysis report

Static analysis result for SHA-256 61a3ca623f0f4248…

MALICIOUS

PDF

81.0 KB Created: 2021-03-28 11:10:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 9886694c31c23ee9820eff45ae9698f7 SHA-1: 202128bfbb5983fed3fccb2dd972f1687671bcdc SHA-256: 61a3ca623f0f42482cab42fb48c5ec03384440693bd5f837de626406d6311ab4
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 domains, indicating a link farm designed to distribute traffic. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware delivery. While no scripts were explicitly extracted, the PDF structure and numerous external links are indicative of techniques used to redirect users to malicious 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
  • 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://seumenha.ru/123?utm_term=happn+app+free++for+pc PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4501975/normal_5fdbfeb2f3080.pdfIn PDF document text
    • https://nogeduju.weebly.com/uploads/1/3/1/3/131398368/6915917.pdfIn PDF document text
    • https://xizuxikeg.weebly.com/uploads/1/3/0/7/130740292/5766751.pdfIn PDF document text
    • http://sodaapp.pro/xudexovetomogepikazixadoddql06.pdfIn PDF document text
    • http://ionatr.fun/631683551558tryb.pdfIn PDF document text
    • http://mitimewigupito.mypressonline.com/nobel_awards_2020.pdfIn PDF document text
    • http://manthoughtswebsite.website/6450200692m1wdf.pdfIn PDF document text
    • http://instapriz24.online/falawuxinixodugatetizebxvaw.pdfIn PDF document text
    • http://idealicaitaly.site/27090312082u0pob.pdfIn PDF document text
    • https://zonapabudaxaj.weebly.com/uploads/1/3/4/0/134017389/9714158.pdfIn PDF document text
    • https://kesiwupi.weebly.com/uploads/1/3/1/4/131407351/3929562.pdfIn PDF document text
    • http://ziwigosopijulal.mygamesonline.org/xuzab.pdfIn PDF document text
    • https://sujefamop.weebly.com/uploads/1/3/4/7/134762109/95ecb127345838e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4370303/normal_6049a8cd71f20.pdfIn PDF document text
    • http://vazawujuzu.sportsontheweb.net/is_paid_paternity_leave_required_by_law.pdfIn PDF document text
    • https://kofetasug.weebly.com/uploads/1/3/0/8/130874362/3d36b3b11.pdfIn PDF document text
    • https://pofitokibifezaf.weebly.com/uploads/1/3/5/3/135394855/9f7141378c247a.pdfIn PDF document text
    • https://tadafemuge.weebly.com/uploads/1/3/4/4/134480681/3214ccdd.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/jezekemunidup/dental_implant_guide_sleeves.pdfIn PDF document text
    • https://s3.amazonaws.com/zukogi/aafes_vendor_information.pdfIn PDF document text
    • https://s3.amazonaws.com/tobovunoberiki/84512528444.pdfIn PDF document text
    • https://s3.amazonaws.com/tawosutosuxi/tuwezaxililub.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_off0000f342.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF342 4420 bytes
SHA-256: a876f7541ca09ea368931c493432406d3e31c7e16e4a8f3dc88b564b2648a6ed
font_01_sfnt_off0001023d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1023D 10724 bytes
SHA-256: 25cf664ce3c87d7535599c6302b6a8f1b7175cc9fab7c95c54498c3ee715485f
font_02_sfnt_off000126f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x126F9 4324 bytes
SHA-256: 1158d95dac44631f497756703988ba3645251422e7ff0015d3fca430225e7c3e