Malicious PDF — malware analysis report

Static analysis result for SHA-256 733c44cb7b706730…

MALICIOUS

PDF

84.4 KB Created: 2021-03-19 18:50:34 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-02
MD5: 83946d16b78e3ad7a296344daecb76f0 SHA-1: 9208b9c9a7d6c79e32bc898299b2e70b799c5511 SHA-256: 733c44cb7b706730f348f6b1a173ff415d79aaac166dd992efa13eae6d675ec0
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains a large number of external links, many hosted on disposable domains, indicating a link farm or SEO spam operation. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. The embedded URLs and the nature of the heuristics point towards an attempt to drive traffic to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

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 contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • 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://zajinet.ru/aws?utm_term=how+do+i+make+a+table+on+google+docs PDF link annotation
    • https://rikizanasurixa.weebly.com/uploads/1/3/1/3/131379420/d585ae3b670.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4484633/normal_604ca20996ba3.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4485310/normal_600290ef9acde.pdfIn PDF document text
    • https://cdn.sqhk.co/savageven/A3gha9c/stack_the_states_online_unblocked.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4454820/normal_6019a7380b8ca.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4457862/normal_5fde3103921d0.pdfIn PDF document text
    • https://tiselewo.weebly.com/uploads/1/3/1/6/131606631/ninuri.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4381297/normal_6013335e7c5d3.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4445532/normal_60184915451c8.pdfIn PDF document text
    • https://cdn.sqhk.co/rafumufo/VfAjcak/microban_24_sanitizing_spray_covid_19.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4427295/normal_601b3a7f13e41.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4487918/normal_6037eb1789754.pdfIn PDF document text
    • https://cdn.sqhk.co/fokudiwun/mih5A49/zinosajedefewuzul.pdfIn PDF document text
    • https://sebinegovana.weebly.com/uploads/1/3/4/0/134095930/pisupij.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4463808/normal_5fcafa252a149.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4370541/normal_6018654fcf831.pdfIn PDF document text
    • https://pipizodo.weebly.com/uploads/1/3/4/3/134352326/xebejurep-vuzefun-mibozemexujek.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/03843db6-0ac9-47a0-af5e-839c4cd9e24f/wazemirivabapudobina.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/dccd55a1-beb8-4f23-b573-9cab44822b0c/how_to_setup_voice_control_on_xfinity_remote_xr15.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/65408eb4-69e4-4bad-a00b-fbf0056674d8/where_was_forrest_fenn_treasure_found_2020.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/935f69f2-086a-4a2c-9326-bae0a914155c/el_amor_en_tiempos_de_colera_resumen_corto.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e6326f09-c945-47df-b29f-0bd978908cf7/total_quartz_4000_20w50_price.pdfIn PDF document text
    • 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://scripts.sil.org/OFLIn 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_off0000f738.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF738 5420 bytes
SHA-256: ec3f4220d80951b607a502c0c8d22c5f5eb38b8b319cd6014def199343faf959
font_01_sfnt_off000109a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109A7 10612 bytes
SHA-256: 9f1228bad84396e247ab3b3ce2457ff9e69a8677780ebe07798919c7279258e3
font_02_sfnt_off00012e45.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12E45 16388 bytes
SHA-256: 2cadb2ae25cea88cb182acc54f62d1c218aef5f2772c4081b94d5d3cddde1204