Malicious PDF — malware analysis report

Static analysis result for SHA-256 1809e52dbc6cab75…

MALICIOUS

PDF

73.3 KB Created: 2021-09-03 20:17:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 957a95e58cd90ca6219fb2c3e7ba8fea SHA-1: ebb13a70865fc580ff5a17f3afa2d4c78d88016a SHA-256: 1809e52dbc6cab754fc76a68344ea392c034d267f5c9e59b0bdabfc8181c48ba
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous embedded URLs pointing to compromised WordPress sites and other domains, suggesting an attempt to redirect users to malicious content or phishing pages. The presence of multiple PDF link farm heuristics further supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

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://www.inter-tube.co.uk/wp-content/plugins/super-forms/uploads/php/files/797501af10b8c51f4bee3d6879deb3d4/misizowudawetumugaj.pdf
    • http://servauto.fr/img/user/file/78815169272.pdf
    • https://greenbins.ca/ckfinder/userfiles/files/98709622594.pdf
    • http://senseoftourism.dk/userfiles/file/jolerakonozinopofewoda.pdf
    • http://daydeothe.vn/rich_editor/file/lazezitutadew.pdf
    • http://bjallstar.com/upload/file/jalapu.pdf
    • https://advicezone.org.uk/wp-content/plugins/super-forms/uploads/php/files/oo2cdepklrtjbgmsds4g6b90e3/xokutovokeloxatilenubi.pdf
    • http://kleinschadenexperte.de/userfiles/file/dutirefinivonupozisedibi.pdf
    • http://majstrissmt.eu/www-data/file/61144397469.pdf
    • https://www.davidwoodpersonnel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160988018dc27a---fewefunuruxotobevejalokij.pdf
    • https://duext.com/wp-content/plugins/super-forms/uploads/php/files/0bd094d18d944e0acfd9569d1efaf578/lekemapawedixum.pdf
    • http://ourpreferred.com/userfiles/files/kadipaziwo.pdf
    • http://tomnhenryanderson.com/clients/8/8a/8a1068334c160bb49438aafe8043afff/File/70627053139.pdf
    • https://www.nestroots.com/wp-content/plugins/super-forms/uploads/php/files/rmd2gepvfed96hv1vp606l0in6/11872428158.pdf
    • https://qeyeoptical.com/ckeditor/ckfinder/userfiles/files/13883660894.pdf
    • https://lerong.vn/wp-content/plugins/super-forms/uploads/php/files/ff10a84b5774a5903d2d012a7c82d044/64300828835.pdf
    • http://saludocupacionalpso.com/home/wp-content/plugins/formcraft/file-upload/server/content/files/16070c378b2711---nijaropopawugavatenomoxud.pdf
    • https://searchkar.com/ci/userfiles/files/semirefokidofi.pdf
    • https://inchiriereelicopterromania.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160e8bd4a1c6a3---pajavajiz.pdf
    • http://bmhs1963.com/clients/7/72/7286fd37811b7a5dece6e69924e4d5ab/File/71297606876.pdf
    • http://nhatrangpalace.vn/app/webroot/upload/files/jixuvufosiretewareko.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BkSY9tpko7c/uplcv?utm_term=weathering+erosion+and+deposition+quiz+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_off0000bbfa.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xBBFA 16792 bytes
font_01_sfnt_off0000d411.bin
1ca3d0dfffc481a4c2e5ee28fbcddcf0140f53d2181502b2f116f49e81dc46ef
pdf-font-stream PDF embedded font (sfnt) at offset 0xD411 11028 bytes
font_02_sfnt_off0000ed35.bin
abf50a457c002bc818da4e4ce2dbfb3a7b2c7f5ff71da33add2aee94274e0d54
pdf-font-stream PDF embedded font (sfnt) at offset 0xED35 16604 bytes