Malicious PDF — malware analysis report

Static analysis result for SHA-256 587523b462ff1f04…

MALICIOUS

PDF

76.2 KB Created: 2021-05-24 19:54:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-14
MD5: 7735a13fa8e219bc7719efe09bf76de4 SHA-1: d9d3173fa0756bf2c9eb3821ce726eeb099ae622 SHA-256: 587523b462ff1f04f1a9c065f914267c5bb48f62499589742f72a609c967f55c
196 Risk Score

Malware Insights

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

The PDF contains numerous external links, many pointing to SEO-optimized content, and one specific URL (`https://baarspo.ru/strik?utm_term=control+systems+by+ij+nagrath+and+m+gopal+pdf`) is flagged as an SEO redirector for free-download phishing. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the PDF structure itself facilitates the attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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.
  • Image lure linking to an SEO redirector (free-download phishing) high PDF_SEO_UTM_REDIRECTOR_LINK
    PDF embeds an image with little or no body text and a clickable link to a multi-word utm_term / FeedBurner-proxied SEO redirector — the 'free ebook / solution-manual / document download' phishing family that ranks for natural-language search queries and routes the user into a payload/redirect chain. The PDF carries no exploit; the risk is the linked destination. Flagged structurally (image lure + SEO redirector) so it does not depend on a ClamAV/ML signature, and regardless of how many filler text pages the lure carries.
  • 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://baarspo.ru/strik?utm_term=control+systems+by+ij+nagrath+and+m+gopal+pdf PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4366369/normal_6038eb4c466b4.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4373008/normal_60155a4b7fc2a.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4369506/normal_6004cac54f9b9.pdfIn PDF document text
    • https://kawapojironene.weebly.com/uploads/1/3/1/6/131637385/pekav_kikowi.pdfIn PDF document text
    • https://latitidazus.weebly.com/uploads/1/3/4/0/134018806/dibirajotulapavijoga.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4481157/normal_5fe1fae933276.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4390366/normal_605cac1c9541c.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4370286/normal_5fc9b84be476c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4427287/normal_60225b686285f.pdfIn PDF document text
    • https://netivexis.weebly.com/uploads/1/3/4/0/134042514/lenobirive-zovojawobosasiz-lukigigudavuvi.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4408321/normal_603598096d61b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4497687/normal_603d00cee51c4.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4454420/normal_605d118e10a3e.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/wiremeresegikon/viwomojuxisobupofew.pdfIn PDF document text
    • https://s3.amazonaws.com/bitajemisajoz/who_founded_positive_psychology.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e6751155-d5b7-4916-962e-f6b05ecc21ac/percy_jackson_series_3_in_order.pdfIn PDF document text
    • https://s3.amazonaws.com/dowesitobuga/zafegebam.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f7983fd9-3fb3-43c2-b6a9-35bf981c2377/fluke_1750_manual.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/434b8f62-dde3-458b-a074-14f3958c3017/aplicaciones_de_razones_trigonometricas_en_la_vida_cotidiana.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f509ad09-995a-4fbb-8d8e-2dbc0de91d60/lexmark_ms310d_ink_cartridge.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_off0000ebee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBEE 5680 bytes
SHA-256: 00eb1128871f715870441906678ab193fae561a1a3540339f8a6e9c1a4e3047c
font_01_sfnt_off0000ff15.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF15 10512 bytes
SHA-256: 63d3946d5b2f57a3d227d1d551bad07db86c38f8bae63869d66beea7e962e29f