Malicious PDF — malware analysis report

Static analysis result for SHA-256 6440a07920c6f8cb…

MALICIOUS

PDF

83.4 KB Created: 2021-03-20 16:58:15 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: d56c7c791c50d41c7e9e5059cb908b5a SHA-1: 340acabd3753f16206acdfa4ee0a95eb68bf1b32 SHA-256: 6440a07920c6f8cb51d2e7199978b5d5677696c3ea3102f573aafde4886b196f
166 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, with a high-confidence heuristic flagging an invisible link designed to lure users to a suspicious domain. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware delivery. The presence of multiple disposable domains and link farms suggests a campaign to distribute malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

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
  • Image-heavy PDF with invisible link to suspicious domain high PDF_SUSPICIOUS_LINK_LURE
    PDF is a small image-heavy lure with invisible link annotations that send the user to a suspicious high-risk-domain URI. This matches credential-phishing carriers where the visible document is only a prompt and the real collection flow happens on the linked website.
  • 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://midufefew.ru/wix?keyword=ap+biology+projects PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4451556/normal_603fedca17fe7.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4501774/normal_5ffcd3d988c9a.pdfIn PDF document text
    • http://eurostore.info/myths_from_mesopotamia_stephanie_dalleyriyux.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4496816/normal_603dd01a44593.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4368740/normal_6053e0a1d5285.pdfIn PDF document text
    • http://rovepofaji.22web.org/belarus_525_manual.pdfIn PDF document text
    • http://hookup753.fun/farming_usa_2_cheats_iosjpbui.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4447273/normal_601dae5c4647b.pdfIn PDF document text
    • http://securityofusersdevicesonline.site/the_crown_season_3_episode_4_historical_accuracyfcrxc.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4458161/normal_5fd661ab8eb26.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4459025/normal_6005074ed9768.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4453889/normal_5fe641d62da0e.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4485579/normal_5ff6678479957.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4378604/normal_5ff64ee15b77b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4387035/normal_603732d432a94.pdfIn PDF document text
    • http://fewafef.iblogger.org/wheel_of_fortune_template_free.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4415950/normal_5fdc0f5075d45.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4469847/normal_602bf7c0149db.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4467589/normal_5fc9fabdc3f61.pdfIn PDF document text
    • http://nncucuucuc.space/secure_folder_galaxy_s10elnp7v.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://dulubuli.rf.gd/pitetuwuluxerosedusazepas.pdfIn PDF document text
    • http://gasededal.epizy.com/learn_english_in_30_days_through_tamil.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_off0000efe7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFE7 5196 bytes
SHA-256: 9d4438cca189756d8398f34aee28c87718ce110760b6884953e6d9be80421037
font_01_sfnt_off000101b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x101B6 11656 bytes
SHA-256: 85eb03c5aa0da88780f695914386fef5f950b251e304ca575eafaa224b4109be
font_02_sfnt_off000129b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x129B6 16092 bytes
SHA-256: ea75db71c9df7250347a03039f742fcd189f5fc3f08964e696816fa8b5227073