Malicious PDF — malware analysis report

Static analysis result for SHA-256 631b116ea23a60e8…

MALICIOUS

PDF

93.5 KB Created: 2021-09-15 12:53:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 332060d36e262b4ba51cbb9b34847dab SHA-1: 17d160370ab9bc4c3116a75f1bab9aa6e08d907f SHA-256: 631b116ea23a60e81f7e52da7f22713ba60aac7ace3468db85ac76527607079f
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The PDF document was flagged by ML classifiers and ClamAV as malicious, indicating a high likelihood of malicious intent. The presence of numerous external URIs, many pointing to disposable domains and forming a link farm, suggests a phishing or malware distribution campaign. The document body is heavily obfuscated and appears to be metadata rather than user-readable content, further supporting a non-legitimate purpose.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

Heuristics 5

  • 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 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://bccphil.paramedix.biz/uploadfiles/file/zajati.pdf In PDF document text
    • https://faktxeber.com/resimler/files/lamuzaviferikaxetewakeza.pdfIn PDF document text
    • http://sovaimm.it/userfiles/files/87737330976.pdfIn PDF document text
    • http://envisystem.com/upload/userfile/files/fipuvamagujivago.pdfIn PDF document text
    • http://bjerkelunden.org/content/files/userfiles/file///70354719290.pdfIn PDF document text
    • http://fuguchair.com/upfolder/e/files/20210914170610.pdfIn PDF document text
    • http://tano-cable.com/d/files/fitoxigo.pdfIn PDF document text
    • https://www.marjojaspers.nl/ckfinder/userfiles/files/vemixusodosev.pdfIn PDF document text
    • http://bsp-oblspl.org/ckfinder/userfiles/files/9840238646.pdfIn PDF document text
    • http://cbcom.fr/ressource/site-image/files/25844159374.pdfIn PDF document text
    • https://ewt.cz/res/file/xowadironutonilete.pdfIn PDF document text
    • http://citadelcaralarms.com/userfiles/file/lofuludigomafunejarezow.pdfIn PDF document text
    • http://aorganboys.handyfriendship.com/upload/files/37910042696.pdfIn PDF document text
    • https://swagath.co/new/ckfinder/userfiles/files/16010644614.pdfIn PDF document text
    • http://tidomusica.com/uploads/files/202109081338145963.pdfIn PDF document text
    • https://aristi-trap.com/upload/users/files/49813417761.pdfIn PDF document text
    • http://azbuka-d.ru/ckfinder/userfiles/files/89929894990.pdfIn PDF document text
    • http://smcertificationservices.com/userfiles/files/folukebib.pdfIn PDF document text
    • http://eco-versute.com/app/webroot/ckfinder/userfiles/files/nimoxibapamikifavoju.pdfIn PDF document text
    • https://xn--80adj7cxa.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/5b271c191e94d17f81e25929a914d089/53887961910.pdfIn PDF document text
    • http://www.gonouvellezelande.com/files/21765684079.pdfIn PDF document text
    • http://xn--80akij1ajew.xn--p1ai/wp-content/plugins/formcraft/file-upload/server/content/files/1613e1e3207671---zugupubevibuk.pdfIn PDF document text
    • http://kiiga.ru/userfiles/file/jozip.pdfIn PDF document text
    • https://proetcontra.hu/userfiles/file/sinaderafadesuwenanuk.pdfIn PDF document text
    • https://stpatswatertown.org/ckfinder/userfiles/files/fomaragegefitubixajetama.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=best+3d+game+maker+for+androidPDF link annotation
    • 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://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_off0001048a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1048A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00011c9c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C9C 19148 bytes
SHA-256: e1d583e9e9f03d6f399c6be0e1a6bd84054d083c652f5667af00a301f0d34532
font_02_sfnt_off00014f3e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14F3E 10968 bytes
SHA-256: 704333193f58c6f3a6baf35f31655a0e941c3bcbece8614d5be77ae4de3f57d4