Malicious PDF — malware analysis report

Static analysis result for SHA-256 7fd5e3819e7962ce…

MALICIOUS

PDF

70.4 KB Created: 2021-09-24 15:58:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 3fd234e5b09ee96c6c36518a6b84564f SHA-1: a07dba80a97003aa92de3ab2758200e9e9d63098 SHA-256: 7fd5e3819e7962cece917032c3276a3914bdf5feafdf965023c6c5ba9de4f006
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs, many of which point to compromised or disposable hosting, suggesting a link farm designed to redirect users to malicious sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware delivery. The presence of multiple link farm heuristics reinforces this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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 link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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 http://b40555.handyfriendship.com/upload/files/berorafi.pdf
    • http://kiko168.com/UploadFile/file/20210908090339866.pdf
    • https://oncallanatomist.org/ckfinder/userfiles/files/lovotatifoliwe.pdf
    • http://xingzhongjing.com/userfiles/file/20210910193619_1979640145.pdf
    • http://smm-mm.com/uploads/news_file/bomimidugavobujexoto.pdf
    • http://flyingwedge.com/uploads/assets/file/bowelul.pdf
    • http://guanzhuli.com/userfiles/file/tujalevixobugizabiti.pdf
    • http://salamatekhanevadeh.ir/ckeditor/files/files/vinajuzonaxabagup.pdf
    • http://dietaltop.com/userfiles/files/nosevamepajometowegerire.pdf
    • http://waterlootour.com/FileData/ckfinder/files/20210923_D92E9B6322FA633C.pdf
    • http://pazarziraat.com/userfiles/file/68974693938.pdf
    • http://test.uebersetzungen-nesselberger.de/wp-content/plugins/formcraft/file-upload/server/content/files/16135627af1022---kibuziruzewogo.pdf
    • http://alpanelektrik.com/depo/sayfaresim/file/98047714818.pdf
    • http://bfr-bialapodlaska.pl/userfiles/file/nutixukimuvirajit.pdf
    • http://htk2.altrodesign.eu/ckfinder/userfiles/files/84934191699.pdf
    • http://prodesign31.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1614ce80547ac4---zapepawutujitevinutuxalip.pdf
    • https://coolinterier.sk/upload/files/fexusumunozasuxefe.pdf
    • http://4998horo.gmmwireless.com/contents/files/32118111742.pdf
    • http://thepokewave.com/uploads/files/94721904220.pdf
    • https://sunarchegypt.com/userfiles/file/39975043554.pdf
    • https://energiadirect.pl/application/resources/ckfinder/userfiles/files/88051403727.pdf
    • http://gennarimaq.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1612eec6b243c4---dujikufopagabusibotuwase.pdf
    • http://tiyuchangdi.com/upload_files/files/20210904_092852.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=doc+scanner+download+apk
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b36d.bin
a0c161837fe64b858edc1fae489ec7f0e81bc42bf51b6aa605bd37465dd6c45c
pdf-font-stream PDF embedded font (sfnt) at offset 0xB36D 16044 bytes
font_01_sfnt_off0000dc1e.bin
182d746d9530f12e4f1df7bfe3553cdc3403559c5a79b936d64a9f4ae7eba72c
pdf-font-stream PDF embedded font (sfnt) at offset 0xDC1E 10496 bytes
font_02_sfnt_off0000f422.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF422 16792 bytes