Malicious PDF — malware analysis report

Static analysis result for SHA-256 988db5cdf71e6e94…

MALICIOUS

PDF

84.6 KB Created: 2021-09-15 19:11:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 0bdc7739ad1a91e55bee55ddd49d9a6d SHA-1: 3c8c98384ba9c3a0ceb65e9c8090c3337b342288 SHA-256: 988db5cdf71e6e94a4862be288a0e49ebac46a0057469cd749c3a9178d349ad2
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable domains, indicating a link farm designed to manipulate search engine results or redirect users to malicious content. The ML classifier strongly flagged this PDF as malicious, supporting the assessment of a malicious intent. No scripts were extracted, and the document body was unreadable binary data.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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 https://massagetheory.ca/wp-content/plugins/super-forms/uploads/php/files/108693757c31e957b8f6ce173c673cd9/vujexifarojibika.pdf In PDF document text
    • https://www.sevgiliyevideo.net/wp-content/plugins/formcraft/file-upload/server/content/files/1613499ee4b67e---6656059777.pdfIn PDF document text
    • http://wgadget.com/file_media/file_image/file/gibazobitoxurukawi.pdfIn PDF document text
    • http://learningkey.org/userfiles/firifitajilozusenug.pdfIn PDF document text
    • http://www.astmalek.cz/obrazky/file/21048846055.pdfIn PDF document text
    • http://enotecagaribaldi.it/userfiles/files/gabegidex.pdfIn PDF document text
    • http://wib24-admin.de/uploads/file/19109170619.pdfIn PDF document text
    • http://www.motionmantra.com/userfiles/files/71640896293.pdfIn PDF document text
    • http://itemclinicchina.com/ckupload/files/xabarezipatugusimikoxu.pdfIn PDF document text
    • https://juniorclublivorno.com/sitonews/images_upload/files/kowedoletosupubis.pdfIn PDF document text
    • https://onecre.com/images/content/files/retuwusajo.pdfIn PDF document text
    • http://vasvaripalmuzeum.hu/upload/file/budodakugufivuzufizod.pdfIn PDF document text
    • http://www.leesii.com/wp-content/plugins/formcraft/file-upload/server/content/files/161342975c5b8c---85430271007.pdfIn PDF document text
    • http://touristclub.in/userfiles/file/37838044609.pdfIn PDF document text
    • https://alsultantrading.ae/userfiles/files/54270771102.pdfIn PDF document text
    • https://fetogram.com/images/upload/files/bazuxiwetidekikokefejo.pdfIn PDF document text
    • https://economiadecomunion.net/ckfinder/userfiles/files/39888996283.pdfIn PDF document text
    • https://unique.global/wp-content/plugins/super-forms/uploads/php/files/af0382c4bf3b802bdcffd300c27e399d/dutukuf.pdfIn PDF document text
    • https://pensiuneavalentina.ro/app/webroot/file/93588645601.pdfIn PDF document text
    • http://fujieshubao.com/zk/UploadFile/file/2021091515310373499.pdfIn PDF document text
    • https://falconshipping-uae.com/userfiles/files/ruzawosisadifo.pdfIn PDF document text
    • http://mascotdd.com/file_media/file_image/file/36160284774.pdfIn PDF document text
    • http://emeraldcovepartners.com/_data/images/file/xatokaberixudikop.pdfIn PDF document text
    • https://sca-eagleegg5k.com/ckfinder/triplebuserfiles/file/63999904778.pdfIn PDF document text
    • https://dom4m.com/userfiles/files/67356310327.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=5+letter+words+that+start+with+t+and+end+in+ePDF 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_off0000e4c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4C5 10468 bytes
SHA-256: 9c986bf60a99bd6969364e93861ff0e9e4e52130d284b741a9ab4f37aa1a5f68
font_01_sfnt_off0000fc8a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC8A 18560 bytes
SHA-256: 53ee71a8f31a898ab6adcfda943dc7c469e2f031f5d58d9800b6cb67aa8a09a5
font_02_sfnt_off00012ca3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12CA3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1