Malicious PDF — malware analysis report

Static analysis result for SHA-256 82e1d8a345126828…

MALICIOUS

PDF

68.8 KB Created: 2021-09-18 12:32:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 07d5ce24d53986574c5b43dc14584327 SHA-1: 7e91473e9d961eda309e97c30c922a971581e45e SHA-256: 82e1d8a345126828b7f75b169d2dc8a4d0614eb8b6045eb45a5b87683a0dfe24
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and is flagged as malicious by ML classifiers and ClamAV. It also exhibits characteristics of a link farm, with numerous external URIs pointing to other PDF files, suggesting a phishing or malware distribution campaign. The embedded JavaScript likely facilitates the redirection to these external resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://tainanrup.longi.tw/uploadfiles/files/20210908_170014_1810.pdf In PDF document text
    • http://joshuadacosta.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d61a1a1226---2695136780.pdfIn PDF document text
    • http://abworder.com/uploads/files/38795102622.pdfIn PDF document text
    • https://palet-school.com/files/files/45623091836.pdfIn PDF document text
    • http://www.mostex.sk/files/articles/file/16555867524.pdfIn PDF document text
    • http://lamorenj.com/userfiles/file/meramoresafofonobewa.pdfIn PDF document text
    • http://xn--80aantfcaehjbxzf1m.xn--p1ai/userfiles/file/91039306333.pdfIn PDF document text
    • http://2m-m.eu/userfiles/files/12966094266.pdfIn PDF document text
    • http://manavpublicschool.org/manav/userfiles/file/47136001306.pdfIn PDF document text
    • http://aczelzalog.hu/tmp/76049988060.pdfIn PDF document text
    • https://bankkartya.hu/js/ckfinder/userfiles/files/depuku.pdfIn PDF document text
    • http://cabinet-blin.fr/ressource/site-image/files/pekadivonub.pdfIn PDF document text
    • http://doingthing.com/downloads/blog/geust/files/20408581847.pdfIn PDF document text
    • https://hilanguage-com-tw.triangle-design.com/files/vazuzijirurosupaj.pdfIn PDF document text
    • http://seksdagen.nl/userfiles/file/21543695207.pdfIn PDF document text
    • https://beysukonaklari.com/ckfinder/userfiles/files/ruxufewepososoritupis.pdfIn PDF document text
    • https://perfecthospital.org/FCKeditor/file/lusefubijaripofam.pdfIn PDF document text
    • https://takarasushimn.com/userfiles/files/25603690191.pdfIn PDF document text
    • https://sportuna.be/ckfinder/userfiles/files/55776360458.pdfIn PDF document text
    • http://alpes-de-haute-provence.proximeo.com/ckfinder/userfiles/files/23947340088.pdfIn PDF document text
    • http://topbuild.net/content/xuploadimages/file/mimubagimipev.pdfIn PDF document text
    • http://sghscsjamarai.org/guruhargobind/userfiles/file/49796370392.pdfIn PDF document text
    • https://hoya.hr/UserFiles/file/jerigelumatalima.pdfIn PDF document text
    • https://movingalpsfoundation.ch/userfiles/file/jimeditisudekelu.pdfIn PDF document text
    • http://mictrogiang.com/userfiles/files/13117690811.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=android+apps+version+historyPDF 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_off0000b03f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB03F 10604 bytes
SHA-256: 3ee264dce10e94a99fc42b28b82205d1271719e6160314e48868369e9feba27d
font_01_sfnt_off0000c877.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC877 15068 bytes
SHA-256: 65c8842ca76f072a2e5f19c3ffd246c75cd17aa63c15ab8af1a009fdb6bf6fed
font_02_sfnt_off0000edee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDEE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1