Malicious PDF — malware analysis report

Static analysis result for SHA-256 f81ac5ad6d02b072…

MALICIOUS

PDF

80.1 KB Created: 2021-09-04 21:36:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-04
MD5: e023342116adc02689fec48177263510 SHA-1: ca6cdf400bbe8c02870cda7fe4bb0ca336590960 SHA-256: f81ac5ad6d02b072b6b3cc8e11ff6ec649fb85d4956b88198836e3d3e983e505
164 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories and presents a deceptive download button. Specific URLs and indicators for this sample are listed in the indicators section.

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
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://siphouse96.com/wp-content/plugins/super-forms/uploads/php/files/ace30950c307c9b02a7fb8d69d6b24e3/tevarotirev.pdf In PDF document text
    • https://bringem.de/wp-content/plugins/super-forms/uploads/php/files/e397f14c77f3f6e128b5931d93e3375d/36523967093.pdfIn PDF document text
    • https://cafe-malaysia.com/contents/file/debaduvi.pdfIn PDF document text
    • https://bentzendesign.se/wp-content/plugins/formcraft/file-upload/server/content/files/160c15cde18ca5---50584640297.pdfIn PDF document text
    • https://llibreriaha.com/img/events/file/wodijaz.pdfIn PDF document text
    • http://opalsolar.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16088d2c04cdd0---tiwifis.pdfIn PDF document text
    • https://thekolkatapackersmovers.com/ckfinder/userfiles/files/11833989729.pdfIn PDF document text
    • http://www.pattyn360.com/upload/forum/files/lugivuxif.pdfIn PDF document text
    • https://fiberglasssupplydepot.com/userfiles/file/motijevumeziwopuvole.pdfIn PDF document text
    • http://www.maarsehoveniers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1609272f0710f4---7817538676.pdfIn PDF document text
    • http://joesservicecenternj.com/userfiles/files/vubozezer.pdfIn PDF document text
    • https://stpetejazz.com/wp-content/plugins/super-forms/uploads/php/files/pfv9d903253r3pd0526i6r5isv/nozanito.pdfIn PDF document text
    • http://vibrosystem.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160b169a76b7da---nepofujit.pdfIn PDF document text
    • http://printrun.nl/userfiles/files/tajebo.pdfIn PDF document text
    • http://consoles-a-gagner.com/fckeditor/userfiles/file/jifovuxitoli.pdfIn PDF document text
    • http://xn--80ackbssfuieecff0e8c.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/kvgs7vg6e1v52br9nj6kksae32/meralisedilefibu.pdfIn PDF document text
    • http://philippinesroadshow.com/wp-content/plugins/super-forms/uploads/php/files/4304124596d66517ad89d6241517f425/voliluzijomiwok.pdfIn PDF document text
    • http://newo.ru/files/files/kibepelanosilofevobujip.pdfIn PDF document text
    • https://sportsht.com/userfiles/file/36232903926.pdfIn PDF document text
    • http://tz5168.com/uploadfile/image/2021/06/27/file/20210627_131306_170.pdfIn PDF document text
    • https://xn--interpeas-r6a.es/upload/files/xejulobidakarudijenapu.pdfIn PDF document text
    • http://kovofilm.cz/userfiles/file/nogudipedi.pdfIn PDF document text
    • https://pannonfinanz.eu/editor_up/wepageno.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=drone+tello+manual+espa%C3%B1olPDF 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_off0000cf7f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF7F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e796.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE796 10628 bytes
SHA-256: 6f82734f8c997d8a3193654eb381df748e30c94af06d982ca4d5ee72ea8aeeab
font_02_sfnt_off0000ff9e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF9E 19064 bytes
SHA-256: a38f6da000ce7a6d15ec98c87822517018b90305159ee7670359392e1cb29841