Malicious PDF — malware analysis report

Static analysis result for SHA-256 4eb623b16f1b9847…

MALICIOUS

PDF

82.9 KB Created: 2021-04-23 13:25:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: bc7e7ee8ac7ef05cc4ed0b7768a60ebd SHA-1: cd09aab63eba9612f9a0ecea5bd3ae38d8dab22e SHA-256: 4eb623b16f1b984775ca8cec89b41b68c3411e387892ec1cf3944899acdbe26b
196 Risk Score

Malware Insights

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

The PDF contains numerous external links, many pointing to a redirector URL, which is indicative of a link farm or phishing lure. The ML classifier and ClamAV detection strongly suggest malicious intent. The presence of embedded URLs and the overall structure point towards an attempt to redirect the user to a malicious site, likely for phishing or to download further malware.

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.
  • 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://midufefew.ru/strik?utm_term=dewalt+dw745+240v+review PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4427498/normal_6008367381bed.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4459926/normal_6015e1ed3d2b6.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4451753/normal_5fdba0f8a2072.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4416938/normal_6053258605f4c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4485800/normal_6039c5ed12bd9.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4490961/normal_600df8eeb217f.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4475580/normal_603c2cab32a2c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4443619/normal_6041ab8a3f4d8.pdfIn PDF document text
    • https://limosajabug.weebly.com/uploads/1/3/0/9/130969130/vunitabawe.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4416151/normal_60118ca8bcc77.pdfIn PDF document text
    • https://sarejazaxixosib.weebly.com/uploads/1/3/4/6/134633098/jawakege-venup-xitumi-giruzupefoxuv.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4445116/normal_60336f7760bc7.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4467927/normal_5fe98f313f269.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4405930/normal_5fe16e6c4139b.pdfIn PDF document text
    • https://zefijevizo.weebly.com/uploads/1/3/2/3/132302816/dinelef.pdfIn PDF document text
    • https://buzowupe.weebly.com/uploads/1/3/1/4/131483044/fuwejal_nutunitaneriz.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4419193/normal_5fefdb424f787.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/dofufiri/give_me_a_reason_piano_sheet_music.pdfIn PDF document text
    • https://s3.amazonaws.com/zamuriza/38569271218.pdfIn PDF document text
    • https://s3.amazonaws.com/timeziso/blank_clock_sheet_ks1.pdfIn PDF document text
    • https://s3.amazonaws.com/zagapaxa/abnormal_psychology_butcher_17th_edition.pdfIn PDF document text
    • https://s3.amazonaws.com/mefovu/agreements_opposed_to_public_policy.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_off0001090a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1090A 5356 bytes
SHA-256: b44a71bf8c57cb9d1edc3acce949c0f7e6f91cf9f2a451e8461d5e571ef6e839
font_01_sfnt_off00011b85.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B85 10256 bytes
SHA-256: be4c62e53cda135df5d0229e512e02ac34d2fe97751222a18d8a95b0cb50e615