Malicious PDF — malware analysis report

Static analysis result for SHA-256 9cd02c2e0867e2ac…

MALICIOUS

PDF

84.7 KB Created: 2021-04-07 18:03:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 0b399aa63a10cc227b92c8e708b6ca0c SHA-1: 7c7e18576cf08e3c9b963f2b93bc2600e3efc39b SHA-256: 9cd02c2e0867e2ac22efe534a952fc254c5f7dc7be4700372efe6de4cc898f3b
254 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains a large number of embedded links, many of which point to redirector infrastructure like 'yafferge.ru'. This indicates a link farm designed to direct users to potentially malicious content. The ClamAV detection and ML classifier further support its malicious nature, classifying it as a phishing trojan.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • 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://yafferge.ru/wix?keyword=introduction+to+ecology+skills+worksheet In PDF document text
    • https://sifufunozomelu.weebly.com/uploads/1/3/4/7/134764248/f06e9a2.pdfIn PDF document text
    • http://nepatokada.mypressonline.com/30742363544.pdfIn PDF document text
    • http://ligumexijigab.getenjoyment.net/how_does_apple_airport_time_capsule_work.pdfIn PDF document text
    • http://liwitesuzemumex.sportsontheweb.net/47007661335.pdfIn PDF document text
    • http://ninuxalezopo.getenjoyment.net/47513575064.pdfIn PDF document text
    • https://zutegikovepob.weebly.com/uploads/1/3/4/0/134017150/wiwufedovotut.pdfIn PDF document text
    • https://folemazilepi.weebly.com/uploads/1/3/1/1/131164248/wisamabimisaf.pdfIn PDF document text
    • https://wafukereloxajof.weebly.com/uploads/1/3/5/3/135311523/vinanoxugi-tiwod-nomusokagi-podupawome.pdfIn PDF document text
    • https://disadoxamegipu.weebly.com/uploads/1/3/4/5/134527150/6716566.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/fobupojowojon/wibetibo.pdfIn PDF document text
    • https://s3.amazonaws.com/dazovosugev/sikawojilaxuperozinabek.pdfIn PDF document text
    • https://ad9e3d1f-bb22-46ca-892e-b6aa3325a756.filesusr.com/ugd/837d34_ae2d7ea4cd88435ca3ed0954ed575fc3.pdf?index=trueIn PDF document text
    • https://4590046d-f0a9-4171-b8a0-56ff8c1fe63c.filesusr.com/ugd/0bfb20_ddd3e35c86c844a9b616bea0376e6fe6.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/doxifuba/chevrolet_volt_2017_owners_manual.pdfIn PDF document text
    • https://c7972686-9310-4d97-8ac3-15e828887225.filesusr.com/ugd/8a419d_8862faf8cacc42fb98c036a4ce5660c3.pdf?index=trueIn PDF document text
    • http://wulibazosuxib.onlinewebshop.net/93859722585.pdfIn PDF document text
    • https://s3.amazonaws.com/wetowuzuxit/airtel_kannada_ringtones.pdfIn PDF document text
    • https://s3.amazonaws.com/rutufokedizon/zokadadasam.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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f640.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF640 5188 bytes
SHA-256: 5f5015df2ae8c8ca74c8ee08c1bb6a93fa7fb55e786bc3bae651079e9b5dbbe5
font_01_sfnt_off000107fb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107FB 11036 bytes
SHA-256: 6009d2c8a780cbee0e8550360025cd6ba64d3b775e06f4a3bb00a92fffd7a535
font_02_sfnt_off00012db8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12DB8 16312 bytes
SHA-256: 531e37f64a2e7dc3bfb257675d9e6c644c7b1597f33ba9a969cd005a7ed65660