Malicious PDF — malware analysis report

Static analysis result for SHA-256 0a33440b29405f8e…

MALICIOUS

PDF

83.9 KB Created: 2021-06-26 01:22:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a62f4d660f4ace6d5acf48ad098f9f75 SHA-1: d18e5766a1850da34376e6f42eadc030feebbf8b SHA-256: 0a33440b29405f8e4e7e5a07e631a1524fb690a7e80b8346c3b81fa16b2a84d0
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous embedded URLs, many pointing to compromised WordPress sites or disposable hosting, forming a link farm. The primary purpose appears to be redirecting users to external sites, likely for phishing or to download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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
  • 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 https://nomylo.ru/uplcv?utm_term=how+to+suck+a
    • https://summit-christian-academy.com/scauserfiles/files/16102934833.pdf
    • http://springswellness.net/wp-content/plugins/formcraft/file-upload/server/content/files/160a95e83906a7---lopalowexesirotabukideje.pdf
    • https://www.bluegreenshouseboats.in/wp-content/plugins/formcraft/file-upload/server/content/files/16080235ab1cfd---towulusixixadisinexi.pdf
    • https://www.bouwenaaneensterkwerkgeversmerk.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160982a7110ece---vokiwadipekose.pdf
    • http://spoilersmensgolfclub.com/clients/865201/File/12916941958.pdf
    • http://alkanboya.com/files/file///93412782277.pdf
    • http://bioident.pl/photos_fck/file/rilojuxajitutipe.pdf
    • http://alemotta.com/resources/original/file/gunatuzuxot.pdf
    • https://www.higher-energy-trampolineclub.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c2c097b13e1---29180488872.pdf
    • http://vce34.ru/attachments/file/worejerenaj.pdf
    • http://allamericannursing.com/userfiles/file/vovamalugumux.pdf
    • https://fmpride.com/wp-content/plugins/super-forms/uploads/php/files/45c886b3b349a97834d5e4dbc865c2cd/fosipivibubidiv.pdf
    • http://ascensionchina.com/userfiles/file/11193240044.pdf
    • http://clinicacomciencia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a7be40c7a62---zejut.pdf
    • https://aadhaarretail.com/administrator/imagetemp/file/56116955170.pdf
    • https://hightechrustremovers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160d1f32831e31---79022163557.pdf
    • https://photographerin.agency/wp-content/plugins/super-forms/uploads/php/files/b2h759aolmbsrki4251jngk645/11584711088.pdf
    • https://stefandes.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b9a6643d09e---94955557110.pdf
    • https://www.diktu.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607289a70311a---xaburulubizamer.pdf
    • http://bilagroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/160812a38145be---86019380859.pdf
    • http://zionhillfirstbaptistchurch.com/clients/73368/File/bajuzuwanibukowizo.pdf
    • https://maydongy.com/wp-content/plugins/super-forms/uploads/php/files/d77lja7lr2pechn66fqqp3huig/tazedeb.pdf
    • 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_off0000ea57.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEA57 16792 bytes
font_01_sfnt_off00010269.bin
486f88a5a352b4e56aca3d00ac934b6f202b42de23ad314f74b27d5b0463cc44
pdf-font-stream PDF embedded font (sfnt) at offset 0x10269 16272 bytes
font_02_sfnt_off00012c8c.bin
0375ec9bd26607b4d0bf084e431d569c11b765b2f4d0ea81b8fc6837633d6ba1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12C8C 10016 bytes