Malicious PDF — malware analysis report

Static analysis result for SHA-256 e3c47d53e22d5185…

MALICIOUS

PDF

84.6 KB Created: 2021-05-14 18:52:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-10
MD5: 4d0a42e1b799313c222f2df288cda0b5 SHA-1: 8f08ce05f5b740f328b9841bac943d64de905d0f SHA-256: e3c47d53e22d5185fbd84febcbda97abcbfe4f35c8e6abb609af8f0bfb4642b9
186 Risk Score

Malware Insights

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

The PDF file contains numerous external links, a common tactic for link farms and phishing sites, with one URL specifically pointing to a suspicious domain. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery. Although no scripts were explicitly extracted, the PDF structure and embedded links suggest an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://jacksth.ru/strik?utm_term=daily+business+english+conversation+pdf PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4471514/normal_601f66062b3df.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4455669/normal_603a6d204ee76.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4481994/normal_5fe9017f12a00.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4417306/normal_604493493353f.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4368999/normal_601952d9c24a0.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4417140/normal_5fe884163ee77.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4490122/normal_5fda86adceafb.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://71a0d42b-91d5-4e94-9338-ff69ca8a624b.filesusr.com/ugd/e5d5e5_e65e1e4c5d744c3f9deeab49d5c55316.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/a66cb9f0-00d1-4e37-ac25-2b97ec324027/17785666206.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f5207bd7-a605-4db6-a9cc-147639ecd4e5/what_is_john_locke_political_theory.pdfIn PDF document text
    • https://s3.amazonaws.com/moduluzuxikari/have_has_got_worksheets.pdfIn PDF document text
    • https://de315c38-daa2-4293-b666-e554ba9b7d65.filesusr.com/ugd/564d2e_f0900e9b7ce4400fbc26695827f40530.pdf?index=trueIn PDF document text
    • https://e66fc774-3394-4daf-ba4e-06b8397bf223.filesusr.com/ugd/f6d1b9_512562d1bbc54bde86d95464facd09df.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/jiwisigetizoxif/42168042985.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/059dd898-5b77-4cd8-965f-5fe49ac49d31/how_do_i_reset_my_schlage_keypad.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c704c0ab-ddba-4693-bcd1-29a5b8d65641/99753427121.pdfIn PDF document text
    • https://5457524e-bace-410a-9ce7-c8d8bc0eedea.filesusr.com/ugd/f0ffd0_75434ce97a1c427b8ee86554d957a5b1.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/gofiguj/11401240472.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/11ac08b4-3e3c-4847-806b-205bcdee53f5/disopote.pdfIn PDF document text
    • https://c33c3ce4-fa2f-4f19-9477-7a801b41b29e.filesusr.com/ugd/ebbcbd_d3195332882f4ee58e85bb8f4520c963.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/dutimajizowa/sigma_1009_sts_instruction_manual.pdfIn PDF document text
    • https://s3.amazonaws.com/vexosafugunu/software_architecture_patterns_richards.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_off00010c24.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C24 5716 bytes
SHA-256: e7e408dbbd48aac8424e9662bc66b807c03995f375463e3df11ea6fc54ea565f
font_01_sfnt_off00011fa1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11FA1 10992 bytes
SHA-256: fc61a5a4f04cf89ad59d3427553e70b3e389732990ec307b057495ea9c9108a6