Malicious PDF — malware analysis report

Static analysis result for SHA-256 28f580aa509aa0f1…

MALICIOUS

PDF

80.3 KB Created: 2021-06-06 23:52:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 9711460426dc623d87f0d684c20597e2 SHA-1: 3b87e20b9a4d19873f79e38c2e75d18fa909acf6 SHA-256: 28f580aa509aa0f1ce20c5820485415f01ab257604094f13f4e81811c47b88be
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 of which are on disposable hosting and use UTM parameters, indicating a link farm or SEO manipulation tactic. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of a malicious lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9950

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://philabc.ru/pbw?utm_term=mobile+app+wireframe+template+figma PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4414176/normal_60651f7b2c486.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4370288/normal_601bf9e647a93.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4411498/normal_5ffb4fec009ea.pdfIn PDF document text
    • https://fimudelowuj.weebly.com/uploads/1/3/1/4/131455024/a1ec51f64629289.pdfIn PDF document text
    • https://zufitamel.weebly.com/uploads/1/3/5/3/135349526/ed5877b4ad99a.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4476436/normal_6026fbcde2e28.pdfIn PDF document text
    • https://towoxaji.weebly.com/uploads/1/3/0/7/130740158/63e942db.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4417806/normal_5fcee2c93dc8a.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4443598/normal_604ba2832cab8.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4401732/normal_5fe39aad7f0da.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4407100/normal_5feba50cc7c99.pdfIn PDF document text
    • https://zuladaziduvixu.weebly.com/uploads/1/3/0/7/130740320/c6084dc196d.pdfIn PDF document text
    • https://mufuwavujove.weebly.com/uploads/1/3/4/0/134042856/666342837f.pdfIn PDF document text
    • https://besavikeneg.weebly.com/uploads/1/3/2/8/132815808/gazulalifi_mefapetimomo_dozuwejuxa.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4377109/normal_601fbba4bbd0a.pdfIn PDF document text
    • https://nibafowezibinax.weebly.com/uploads/1/3/4/3/134319588/4839045.pdfIn PDF document text
    • https://xonedanafesiliw.weebly.com/uploads/1/3/4/6/134633415/9662123.pdfIn PDF document text
    • https://wivapofeselaf.weebly.com/uploads/1/3/5/3/135317026/a72aa319e34.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://uploads.strikinglycdn.com/files/2206f3ac-a91d-476a-a35b-7cb184ea2273/how_does_the_grand_inquisitor_die.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/bac0ecb6-cca9-4fe6-8489-f8f5214421ad/why_does_my_dyson_dc44_keep_stopping.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7cc6ae2b-c07d-45a9-b660-6b4517b65f1b/76376604040.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ae97a359-0bcb-4072-a007-453af4bdb648/gogiforofapoxekitokuzodu.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a023fec2-f147-4a95-9321-830b8d07c782/how_to_adjust_g_shock_for_daylight_savings_time.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a53ab0de-58f8-408e-a27e-5f8f5bb89c1e/57362606432.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1f3d8e2a-4d4b-41a3-bca6-69d9aaa7fb68/fafunafadetofoxofusigopaz.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/fc1f28b4-3859-4be8-8140-083ad3754ed9/85405671555.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e2729a8b-0c72-4e37-bd20-e106dab4c541/rheem_rbha-21_specs.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_off0000efca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFCA 4964 bytes
SHA-256: ef08b0fc64a6e784df68281ea01ae03f706e244356a973496a2263930e4d434e
font_01_sfnt_off000100be.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100BE 10620 bytes
SHA-256: 11e359ec105066e26e940fde2f4fc6f06ca53e1bd74330653d5282bad636318c
font_02_sfnt_off0001250c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1250C 4324 bytes
SHA-256: 4fcfa7c68d76e23b667942a3ac892d2d5d88346478daafc61479ad4df4af3dd3