Malicious PDF — malware analysis report

Static analysis result for SHA-256 e55aab318c74bf8b…

MALICIOUS

PDF

81.2 KB Created: 2021-09-08 20:44:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 0243cfb7e9972035a0559dfdf339f639 SHA-1: c56ae2f91afc0b8519c7951eb2d52bbed09e0913 SHA-256: e55aab318c74bf8bd9b4250243eb21f2149180cdc202a12cca4dd50ea8ec1b8b
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ClamAV and an ML classifier, and exhibits characteristics of a phishing lure. The heuristic 'SE_PASSWORD_ARCHIVE_LURE' indicates the document likely instructs the user to open a password-protected archive, a common method to conceal malicious payloads. The presence of numerous URLs, many pointing to disposable hosting or compromised CMS uploads, further supports a malicious intent to distribute further stages or phish credentials.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Password-protected archive handoff high SE_PASSWORD_ARCHIVE_LURE
    Document gives password instructions for an archive or attachment — often used to keep payloads encrypted until after gateway scanning
  • 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://icrs-as.com/userfiles/file/bujefekeselefaxedawale.pdf
    • https://edex.co/userfiles/files/89720408281.pdf
    • https://laplacedesstores.com/upload/file/fowazigijotodisepe.pdf
    • http://gabident.pl/local/userfiles/file/27560577492.pdf
    • https://strategieb2b.com/userfiles/file/bojotajipekapuzit.pdf
    • https://comillaspostgrado.es/userfiles/file/kakowexuk.pdf
    • https://vegan-eshop.cz/data/file/19168901236.pdf
    • http://gr-chem.com/upload/files/45366664404.pdf
    • http://easternhoteljeju.com/FileData/ckfinder/files/20210903_D53633A17FDFAFE6.pdf
    • https://aiwcecckolkata.org/FCKeditor/file/41092579453.pdf
    • https://kurek-rowery.pl/user_pict/file/45455884556.pdf
    • http://schodylux.pl/userfiles/file/53087499636.pdf
    • http://coytex.net/ckfinder/userfiles/files/44089117957.pdf
    • http://thrifty-uy.com/files/others/25531771687.pdf
    • https://www.pfgpartners.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16133d01c726e1---65256832064.pdf
    • http://le-lemniscus-incandescent.fr/ckeditor/upload/files/57663847590.pdf
    • http://vasilii-orlov.fun/wp-content/plugins/super-forms/uploads/php/files/9fbaceda94fdf2049fb89b24d484d40b/gabab.pdf
    • https://creativesilhouettes.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16134990ace778---59555863779.pdf
    • http://residencelesaline.it/userfiles/files/48560897081.pdf
    • http://labotinnghia.com/img/files/78998975012.pdf
    • https://hanakspotrebice.cz/eshop/ckfinder/userfiles/files/ponaziv.pdf
    • http://shortguycentral.com/ck_uploads/files/48400939055.pdf
    • http://duet-czluchow.pl/userfiles/file/kawajoxosasuvu.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=password+protected+pdf+cannot+print
    • 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_off0000d869.bin
b0b5dfb4e6abda3866fcdd48a1d39cdd6de3140273838117d998a6af270a325d
pdf-font-stream PDF embedded font (sfnt) at offset 0xD869 17608 bytes
font_01_sfnt_off00010644.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10644 16792 bytes
font_02_sfnt_off00011e5b.bin
842923ccf0002bf6a293c7573c2f1c25ac55ae76483a08c7c64512583feaa586
pdf-font-stream PDF embedded font (sfnt) at offset 0x11E5B 10656 bytes