Malicious PDF — malware analysis report

Static analysis result for SHA-256 158ded91c6b26b6e…

MALICIOUS

PDF

72.2 KB Created: 2021-02-16 17:18:08 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-15
MD5: 01a15cb9e94c79dc2b3255f2fd0b9814 SHA-1: d21ad1a4dca58d28979255a99dc5bfad458ec134 SHA-256: 158ded91c6b26b6eb6a5c547b323c443658f3cccee68266f60daccf3684de94f
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 malicious sites. The primary lure appears to be information about smoke detector issues, leading to a phishing site. 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://leonvi.ru/strik?utm_term=kidde+smoke+detector+beeps+3+times PDF link annotation
    • https://cdn.sqhk.co/nogawevorus/jja8ibq/publix_weekly_ad_merritt_island.pdfIn PDF document text
    • https://cdn.sqhk.co/vimerokil/x0qjiRn/instagram_captions_for_selfies_short.pdfIn PDF document text
    • https://towodoruzaxigol.weebly.com/uploads/1/3/6/0/136050186/26f3e5db.pdfIn PDF document text
    • http://xivusolokedujes.22web.org/folividoteb.pdfIn PDF document text
    • https://zesudegefomoga.weebly.com/uploads/1/3/1/0/131070027/4737050.pdfIn PDF document text
    • http://like-store.site/pdf_tkb_guru_agama_islamt0k2l.pdfIn PDF document text
    • https://forozuzatopu.weebly.com/uploads/1/3/1/8/131858118/2239587.pdfIn PDF document text
    • https://cdn.sqhk.co/tutabalero/RFhbha3/85689338675.pdfIn PDF document text
    • https://betirowi.weebly.com/uploads/1/3/4/6/134661799/7295061.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4374376/normal_60195ef2b010b.pdfIn PDF document text
    • https://cdn.sqhk.co/puxedimuwo/cjjP3ha/gepurufotufixe.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/sogovekevi/jepozudafowufega.pdfIn PDF document text
    • https://s3.amazonaws.com/punurum/android_studio_switch_kotlin_to_java.pdfIn PDF document text
    • http://nevigewiba.epizy.com/11540971412.pdfIn PDF document text
    • https://s3.amazonaws.com/divikufifir/vewotowifoxerise.pdfIn PDF document text
    • https://s3.amazonaws.com/pobixedele/mopepezosaveturuguzox.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_off0000dd3b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD3B 5312 bytes
SHA-256: e6a4ae3f7ae298dc28867b7a0ae4a45d6882853877aa95f67da7b7d0da0603d8
font_01_sfnt_off0000ef3a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF3A 10656 bytes
SHA-256: 61067aa6957d4943695fb95f37867ee4551f5d85fd8939fe56ae051dd1e322a5