Malicious PDF — malware analysis report

Static analysis result for SHA-256 4596d50998fd8a40…

MALICIOUS

PDF

75.6 KB Created: 2021-03-17 14:59:41 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: d6cd672f9ae1b63c4bce91cf6e119ebe SHA-1: 2189caef51ca44814183d2a407f0d745b278db9b SHA-256: 4596d50998fd8a401360fd0b31e5d060fb18b56695d54b91634c4ab004847e0b
196 Risk Score

Malware Insights

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

The PDF contains numerous external links, many of which are part of an SEO link farm designed to redirect users to potentially malicious content. The primary lure appears to be a 'Bus 192 schedule pdf', which is likely a pretext for a phishing attack or to download a second-stage payload. The ML classifier and ClamAV detection strongly indicate malicious intent.

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://zajinet.ru/123?utm_term=bus+192+schedule+pdf PDF link annotation
    • http://italystore.pro/tiwajibikubipodotafig03zs.pdfIn PDF document text
    • http://biomaniix.website/minavakirijelebiledurapogcbq0.pdfIn PDF document text
    • http://goodsfor.life/how_much_ferrari_testarossap8wr4.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://7ef5d8b8-74ac-4e0a-b0a0-fa61ca6462a8.filesusr.com/ugd/23e9be_4206664fdfc2407bbaea79912be306c6.pdf?index=trueIn PDF document text
    • https://af1bea64-f5cd-41c2-a7c1-97f21c1aa057.filesusr.com/ugd/592671_aea79032561d4049931ab0dd9a7adb2e.pdf?index=trueIn PDF document text
    • https://78e27e65-9996-4239-a63d-7a21722db537.filesusr.com/ugd/03f576_3be8650e16704b169cf65788fd8c55ca.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/jivagajamav/bunelel.pdfIn PDF document text
    • https://1b6fbac1-9b66-4609-9151-81f5d4c316f7.filesusr.com/ugd/5e81b9_bc5948197b0342589e2cad1fa8c75aaa.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/forupokisip/72392779037.pdfIn PDF document text
    • https://eb40363d-1d1f-4170-a897-f23f0f433116.filesusr.com/ugd/2a1429_e41a791d0cbd44c69e941854dff34528.pdf?index=trueIn PDF document text
    • https://47ab6ce1-aee6-4086-a8e7-31fe393d2411.filesusr.com/ugd/afbef4_d7a2d3d1ef7744dc9ff445e8ed7c9cd0.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/fewunadupop/persuasive_advertising_techniques.pdfIn PDF document text
    • https://45b0b119-5f8c-43e7-b437-4e12d17c1c81.filesusr.com/ugd/3826db_ba480e9c83c247278a7591b41f7e6fd2.pdf?index=trueIn PDF document text
    • https://601bead5-a720-4f65-98db-62fe2a42cb91.filesusr.com/ugd/0e52b4_8b450221497d4eb4aae0a22de0a9fc1d.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/muvevanepen/85777552268.pdfIn PDF document text
    • https://7f1888b6-cdab-4603-9914-1cf81a8b29aa.filesusr.com/ugd/6846fe_5c1148836ca94583a2aa84413ff0ff24.pdf?index=trueIn PDF document text
    • https://4123e755-5e7e-4fb8-b167-49ba90d37259.filesusr.com/ugd/fd3290_38f8e4b9a5ce40ab9ca9ea1f907ffc5d.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/sigobija/how_to_learn_r_online.pdfIn PDF document text
    • https://245df057-3761-468b-8bc4-2c9c6734f7c7.filesusr.com/ugd/06c8e1_1fd24a38474b494b9ad5719e88829eca.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_off0000e9bb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9BB 5328 bytes
SHA-256: ecbe75d6da731462b575e0016b89df6aa3ea395a359a0e9b03d0cda3936bb9d0
font_01_sfnt_off0000fbe7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBE7 11244 bytes
SHA-256: d12ee26b328926504096b96b72f18cf0e529ae1c25cc076ef85b72a2158ad286