Malicious PDF — malware analysis report

Static analysis result for SHA-256 821975f2bc4a24a7…

MALICIOUS

PDF

84.9 KB Created: 2021-09-22 12:29:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: e3247bd776fbde777d48a0f5d887b61b SHA-1: d2ab345a710057682374368b5747a069d077eb86 SHA-256: 821975f2bc4a24a7041ac00cf8961d51d9cf9d8e95c99af4e7232d77e706afb0
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ClamAV and an ML classifier. It contains numerous links, many pointing to compromised CMS upload directories or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of multiple external URIs and link farm heuristics indicates an attempt to lead users to external, potentially harmful, websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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 https://grahampropertytax.com/wp-content/plugins/super-forms/uploads/php/files/271d5dfee77d44c0d70495d76492a68b/vigusijegaluzapavewete.pdf In PDF document text
    • http://leaguengn.com/userfiles/file///fategupolam.pdfIn PDF document text
    • http://aajude.pt/backoffice/ckfinder/userfiles/files/kakisusumedifodegikedowa.pdfIn PDF document text
    • http://biogenetec.tw/image/files/20210913_151852.pdfIn PDF document text
    • https://orkhaconstruction.com/wp-content/plugins/super-forms/uploads/php/files/43fies84v3pf7768a7du0m7jeo/10905172443.pdfIn PDF document text
    • https://nedimgame.net/calisma2/files/uploads/kuxilalixozuxumikufidebod.pdfIn PDF document text
    • http://sapientgenerator.ru/files/userfiles/files/13814929666.pdfIn PDF document text
    • http://kleiberit.ru/files/file/65137441661.pdfIn PDF document text
    • http://jshtextile.com/UserFiles/file///51448538517.pdfIn PDF document text
    • https://rt-totaalafbouw.nl/userfiles/file/kakuxuliguwavir.pdfIn PDF document text
    • https://www.prowallpanama.com/wp-content/plugins/super-forms/uploads/php/files/697dd01d83ca6693931bffb28de39fd8/63036467832.pdfIn PDF document text
    • http://broadviewlibrary.org/uploaded_bvlib/file/nabufojevesegikeluwadaju.pdfIn PDF document text
    • https://www.notusweb.com.br/ckeditor/ckfinder/userfiles/files/56584573590.pdfIn PDF document text
    • https://tranhdaquyhn.com/uploads/news_file/57936138629.pdfIn PDF document text
    • http://irmascaritasdejesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/1612f5995f2dfa---24156193826.pdfIn PDF document text
    • http://chiaranannini.com/userfiles/files/92312443125.pdfIn PDF document text
    • http://macro-e.com/app/webroot/userfiles/files/31182578370.pdfIn PDF document text
    • http://www.thebetterinsurance.com/wp-content/plugins/formcraft/file-upload/server/content/files/161388f66c7511---matalutemikikuw.pdfIn PDF document text
    • https://icbacademy.com/upload/files/48775511707.pdfIn PDF document text
    • http://longruiglass.com/ckfinder/userfiles/files/20210905_093620.pdfIn PDF document text
    • https://h16hr15k-h19hr37urn.com/contents/files/82519684107.pdfIn PDF document text
    • https://tectrongim.com/uploads/file/39566547510.pdfIn PDF document text
    • http://efeteknikyapi.com/userfiles/files/72114297660.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=ideas+to+do+in+minecraftPDF 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_off0000e903.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE903 17408 bytes
SHA-256: 3608a2c16185c3e6826e43a975c76ff70bdd35fb9ddc80691a208c6ea42d8cb0
font_01_sfnt_off0001165f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1165F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012e76.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12E76 10540 bytes
SHA-256: b1fc7f87477ce1455a6bbf5a9c75a3a7df167c03c50822ff247d680b270b8eed