Malicious PDF — malware analysis report

Static analysis result for SHA-256 167643dba10b2d09…

MALICIOUS

PDF

77.3 KB Created: 2021-09-01 10:02:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 6a72930fdbcde78eafa1e65f418c0178 SHA-1: 5349774167ed4fdd1f3c2c7db24fb0defb70a7b7 SHA-256: 167643dba10b2d09b6473c18c2956477d02f489671714a92a16ad8dc7cf57e70
96 Risk Score

Malware Insights

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

The PDF file contains a link farm, with many URLs pointing to compromised websites and disposable hosting. The heuristic 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' indicates that some links are hosted on compromised WordPress upload storage, suggesting an attempt to distribute malicious content or redirect users to phishing sites. The ML classifier also strongly flagged this PDF as malicious.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9946

Heuristics 5

  • 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://vetranhtuong.info/luutru/files/bavez.pdf In PDF document text
    • https://vanvoorst.info/uploaded/file/36610629077.pdfIn PDF document text
    • https://suhrsmad.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160adbc5c52e43---5229220355.pdfIn PDF document text
    • http://clinicaveterinariailmarzocco.it/userfiles/files/6209726488.pdfIn PDF document text
    • https://arerp.kr/data/file///laxijijetu.pdfIn PDF document text
    • http://kag.fr/userfiles/file/ganoguwore.pdfIn PDF document text
    • https://pgprojekt.pl/Upload/file/fumalovami.pdfIn PDF document text
    • https://www.olympusnorge.no/wp-content/plugins/super-forms/uploads/php/files/dvt1pgl5ai90cdfud67g4eiift/74071659555.pdfIn PDF document text
    • https://www.shopveriamici.com/wp-content/plugins/super-forms/uploads/php/files/anuqtd06jm6sblaf6savi1vnj9/819854629.pdfIn PDF document text
    • http://jatyn.cn/upfiles/202105/file/1620905867.pdfIn PDF document text
    • http://kfnmdg.com/upfolder/e/files/20210601091110.pdfIn PDF document text
    • https://www.heainc.com/wp-content/plugins/formcraft/file-upload/server/content/files/160dcc4909b909---ninikotaginaxenulewil.pdfIn PDF document text
    • http://mijn-nederland.nl/userfiles/file/61309930027.pdfIn PDF document text
    • https://hondamienbac.vn/userfiles/file/vasebizokobuganig.pdfIn PDF document text
    • http://iamsoldierfit.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8b1195da61---81855735108.pdfIn PDF document text
    • http://gillsandgeckos.com/userfiles/file/wimovebe.pdfIn PDF document text
    • http://www.jasfec.com/imgs/uploads/49603173249.pdfIn PDF document text
    • http://etre-belle.su/images/file/lazowun.pdfIn PDF document text
    • https://nobleanimalsanctuary.org/wp-content/plugins/super-forms/uploads/php/files/tmp/28293023561.pdfIn PDF document text
    • http://veronicanealhome.com/wp-content/plugins/formcraft/file-upload/server/content/files/2/16125746880359---fonasuliluxasefegitisiwux.pdfIn PDF document text
    • https://spaslask.pl/wp-content/plugins/super-forms/uploads/php/files/jcmqsf1rf5jt5adn690a890p4c/litugepukanetemiva.pdfIn PDF document text
    • https://businessservicesuk.com/userfiles/file/sizanimevuna.pdfIn PDF document text
    • https://bwawarszawa.pl/upload/file/xugojexabojomuz.pdfIn PDF document text
    • http://www.majoriscambio.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607e67d0f36f0---xovadazovurusaposeb.pdfIn PDF document text
    • http://stevis.cz/files/file/zuberotiroxamifi.pdfIn PDF document text
    • http://dvarenda.ru/upload/file/42778202066.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=sparknotes+pdf+free+downloadPDF 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_off0000c7e6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC7E6 17324 bytes
SHA-256: 8c1190abb80427157d5f1b9f50c4999e9beeae09c5f0f6ec53efccb82bac0fa4
font_01_sfnt_off0000f4c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4C5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010cdc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10CDC 10652 bytes
SHA-256: 444bbc0e9e3c94b48891159e057fdf93a92b3cc8c8702e008f1df2f2b6f1e087