Malicious PDF — malware analysis report

Static analysis result for SHA-256 dc19c3231e922aed…

MALICIOUS

PDF

75.5 KB Created: 2021-03-17 15:01:14 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-20
MD5: 2e4db0c6787543883b9efe8638e90321 SHA-1: bfd9459ab657f989d657be9bda70be31dffadca7 SHA-256: dc19c3231e922aed00bd6d69e59643f09aece769f9a8bfea9ca1cbbe1be70025
186 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection for 'Pdf.Phishing.Trojan'. It contains a link farm with numerous external URIs, including one pointing to 'baarspo.ru', suggesting a phishing or malware distribution attempt. The ML classifier also returned a high confidence score for maliciousness.

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.
  • 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://baarspo.ru/strik?utm_term=what+words+have+the+long+i+sound PDF link annotation
    • https://vugevosuza.weebly.com/uploads/1/3/5/3/135328642/5780465.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4496605/normal_60411f1c6b465.pdfIn PDF document text
    • http://msertis.xyz/31008495797po10j.pdfIn PDF document text
    • https://betozuwozoz.weebly.com/uploads/1/3/4/1/134108580/gugoxufogawad.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4496389/normal_5fc7f2300e956.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/538827ff-02cc-49d3-80e3-93e6fa2f61bf/vuxazat.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/abf5eea2-1457-4280-8cc8-60f7c282664c/50976319280.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/02253a23-1a52-4a81-a082-18af5c47bff7/liwimamegif.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/af80df8b-1e53-4952-bca7-97a5e0e08103/what_is_the_message_of_girl_interrupted.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f7028366-72b3-4154-926c-aa65e6122508/tukowelokiparokapusaval.pdfIn PDF document text
    • https://6baea7ca-81e4-4a11-8410-716433a99462.filesusr.com/ugd/764aaa_fc1286b6819f409e830aead23640e371.pdf?index=trueIn PDF document text
    • https://dec4a425-646e-450a-80ca-a73a75d058ad.filesusr.com/ugd/ba3095_aacb91633b374c66b55e09de8babda89.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/87bc1cbf-8c8b-4446-ab85-d3a7031b1a97/antenna_and_wave_propagation_balanis.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7f8f04a6-e1a9-40e5-a319-d614e028e52b/briggs_and_stratton_quantum_engine_repair_manual.pdfIn PDF document text
    • https://19aaccd0-9772-41b6-85c4-be118606641a.filesusr.com/ugd/a12125_e45f0d4f60d846288859e892d4930fcc.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/a1e9212a-2de9-4d2e-80f5-e42662f91839/brother_hl_2170w_wireless_installation.pdfIn PDF document text
    • https://0d555108-1732-4721-8d72-76d747b2053a.filesusr.com/ugd/1b0481_c60817808e1241cd8931ab3f73b71135.pdf?index=trueIn PDF document text
    • https://f16fa5c1-8556-4bba-8f86-04d9c108beb0.filesusr.com/ugd/2c3d75_43ba6346fe1e408eb489bda71d9eb1ea.pdf?index=trueIn 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_off0000e94c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE94C 5252 bytes
SHA-256: 5d22c865706d98b487719d38fbef41bcb36ec66f036289a9d5c16485ee0823ac
font_01_sfnt_off0000fb3d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB3D 11220 bytes
SHA-256: e7d7c37cad13d02fe2b30f204bcc3ee5cd2b81c83d3e8d1d803283e2e892255d