Malicious PDF — malware analysis report

Static analysis result for SHA-256 ca65812b170a1ff0…

MALICIOUS

PDF

78.9 KB Created: 2021-09-17 06:57:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f54a5ddaee5b27d2ce59e4e39fa67ad1 SHA-1: 8e5de66a8192c83a5ae899256a2c663b0b6c0d0a SHA-256: ca65812b170a1ff0fe7711d688780dc6a25b2053ddbce9e5f6e92045309844a5
156 Risk Score

Malware Insights

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

The PDF contains a large number of embedded URLs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution through these links. No scripts were extracted, and the document body was unreadable, so the analysis relies on the URL heuristics and AV detection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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
  • 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://philabc.ru/uplcv?utm_term=my+gallery+deleted+photos
    • http://debten.net/UserFiles/File/badobip.pdf
    • http://constructionone.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613e693550539---kewiturekipowapejuj.pdf
    • http://www.hptindia.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e26dba08b2---xomalofiza.pdf
    • http://vuoncotichdep.com/upload/files/wuxekiwobateluzosopa.pdf
    • http://npas.ru/pic/file/22336281172.pdf
    • https://gangnampools.com/contents/files/146153637.pdf
    • https://nicemexico.net/wp-content/plugins/formcraft/file-upload/server/content/files/16143b93ab8493---vujitivabevop.pdf
    • http://signauction.net/userfiles/file/27568077362.pdf
    • http://shannonlakeestates.org/fck_images/file/fenug.pdf
    • http://inoxbienhoa.com/upload/files/vonib.pdf
    • http://bayernglobal.de/userVZ/file/kuvise.pdf
    • http://amghanoi.com/images/ckeditor/files/57668992911.pdf
    • http://invismortgagebroker.com/images/file/84353954447.pdf
    • https://garnizone.com/userfiles/file/ludaw.pdf
    • https://takarasushimn.com/userfiles/files/zonovolomokezimifumap.pdf
    • http://vibrosystem.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1614362a00614d---68797528110.pdf
    • http://cityclick.it/userfiles/files/vopomisamubobax.pdf
    • http://jumpstart.mobi/ckfinder/userfiles/files/xamivorupolor.pdf
    • https://g4m3s-4p1-12s1.com/contents/files/duzizozedewugejoda.pdf
    • http://maynenkhiinverter.com/media/ftp/file/kozumudepowibilofa.pdf
    • http://tcsklife.com/filespath/files/20210910120259.pdf
    • http://www.rannatennis.ee/data/upfiles/files/38780479531.pdf
    • http://yakutiaprime.ru/SITE/files/editor/file/28176524998.pdf
    • https://sapporomn.com/userfiles/files/luravom.pdf
    • 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_off0000d237.bin
1bf36a61beca3732c5bd77bcbcd6dc763575d03be4ba7511faf124ecc713d497
pdf-font-stream PDF embedded font (sfnt) at offset 0xD237 17216 bytes
font_01_sfnt_off0000fe57.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFE57 16792 bytes
font_02_sfnt_off0001166e.bin
cd2ee8ce11e96d6ae849c144951a25ba5268d86ac76b7df7adf8ec83b9134b78
pdf-font-stream PDF embedded font (sfnt) at offset 0x1166E 10580 bytes